Editor's note: Have you uncovered pop culture history? Or are you a collector? Tell us about it in comments at the bottom of the story.
(CNN) -- Like Captain Ahab hunted the great white Moby Dick, Joe Maddalena is hunting ruby slippers from "The Wizard of Oz." The magical shoes have been missing since 2005 when they were stolen from the Judy Garland Museum in Grand Rapids, Minnesota. There is a $250,000 reward for their return.
Maddalena knows where to hunt. He's the owner of Profiles in History, a Los Angeles-based auction house that specializes in highly sought-after movie and television memorabilia, and "Oz" is one of his favorite movies.
Among the many trophies that Maddalena has collected and sold for sums of up to six figures: a T-800 robot used in "Terminator 2: Judgment Day," a golden ticket from "Willy Wonka & the Chocolate Factory" and the iconic car used in "Chitty Chitty Bang Bang" -- all items that are sure to make film geeks drool.
"What I sell is pop culture, it's international currency," Maddalena says. " 'The Terminator' is known all over the world. Cleopatra, Marilyn Monroe -- these figures are international. We have clients from all over the world -- half my clients are outside the United States. It's a very large market, and I think that people really are nostalgic and want to collect things that meant something to them."
The expert collector and his company have been featured on the SyFy series "Hollywood Treasure," which is airing new episodes on Wednesday nights.
Maddalena's journey to being one of the foremost experts in famous props and costumes -- not to mention the star of a reality show -- began early.
"My parents were antique dealers and I grew up on the East Coast. I came to California in the early '80s to go to college and always loved Hollywood and old movies, and always had the interest in it as a young kid."
Maddalena began selling old documents, but his interest in classic literature led him back into a passion for film and television.
"In 1996, my business had been well established in historical documents, and I started selling Hollywood memorabilia right at the time (the restaurant chain) Planet Hollywood took off," he says. "So we were very fortunate to be there at that time and they were clients and we helped them establish and build memorabilia in 100 restaurants. It was kind of the launching pad for my business."
Maddalena began hunting for as much memorabilia as he could find to put up for auction. He notes that, for a time, Hollywood props and costumes "were like disposable waste. The movie or show was a product, and everything else was part of the process. They would sometimes destroy it, or repurpose it."
As "Hollywood Treasure" shows, valuable pieces from beloved films and shows could potentially be found almost anywhere.
"There's a Mexican restaurant right down the street from us. (Profiles in History employee Tracey McCall) noticed a plane on the roof, and the owner said it's James Bond's plane. We literally found (what was believed to be) the plane from 'Octopussy' sitting on the roof of a cantina two miles from our office that I've probably driven by for 20 years," he recalls.
"Treasure's" first episode chronicled the discovery of the carpet bag from "Mary Poppins." It had ended up in the possession of an Illinois family, who used it for luggage. Maddalena also remembers a winery in Malibu, California, that had the wagon from "Planet of the Apes."
Maddalena and his team travel all over the world, tirelessly searching for these items.
"Deckard's blaster from 'Blade Runner' was seen once publicly 15 years ago at a convention. It took me 14 years to find it. We finally found it and sold it for $200,000," he says. "There's a legend that after 'Lost in Space' wrapped, the chariot that looks like a snowmobile was sent to Big Bear, California, to a ski resort. It was decommissioned and used on the slopes. We actually found it. We'll search for years to find these things."
Another Hollywood memorabilia hunter who has searched the globe for years is "Star Wars" superfan and iReporter Gus Lopez.
"As I got into collecting, my interests expanded into other areas such as store displays, cast and crew items, food products, cereal boxes, toy prototypes, lunch boxes and eventually props and costumes used in the films," says Lopez, a Seattle resident.
He now puts most of his efforts into finding "Star Wars" movie artifacts.
"They were acquired from a wide range of sources: crew members, public auctions, reputable prop dealers, friends who want to sell a piece in order to buy another, and even some items thrown out as garbage or left behind at the filming locations," he says. "For example, I took four trips to Tunisia to visit the filming locations for the 'Star Wars' planet Tatooine where I was able to find fiberglass bones from a large skeleton used in the desert scenes from the first movie."
Aside from a massive collection of "Star Wars" toys and a room filled with 1,400 "Star Wars" breakfast cereals from 100 countries, Lopez's collection includes an Ewok mask from "Return of the Jedi," the original Death Star from the first film, "A New Hope," and Boba Fett's backpack from "Jedi."
Lopez calls these props and costumes "the ultimate collectible," and says there is something special about the "thrill of the hunt" when it comes to his hobby.
"Years ago, collecting communities formed at toy shows and through magazines, but today it's dominated by Internet forums covering just about every collecting interest, even the most esoteric," he says. "As a result, collectors build friendships with like-minded enthusiasts all over the world and frequently meet up at conventions, auctions and other gatherings. For example, we've had panels covering 'Star Wars' prop-collecting at the last several 'Star Wars Celebration' conventions, and the panelists consisted of collectors from all over, and most of them have built friendships based on common interests in 'Star Wars' prop collecting."
Many of the collectors bidding at auctions tend to be anonymous, but there are some big names.
"There are a lot of known collectors out there, George Lucas and Steven Spielberg, for sure. A lot of rock stars collect," says Maddalena.
Nicolas Cage was recently in the news after his copy of "Action Comics" No.1 -- one of around 100 in existence, which include the first appearance of Superman -- was recovered by police after being missing for 11 years. (The book is still being held by police. Among the comics still missing is a copy of "Detective Comics" No. 27, which introduced Batman.)
The man who put together Cage's collection of comics, Stephen Fishler, is the creator of ComicConnect.com, which itself has been in the news several times in recent years, for selling items like the highly-sought-after "Action" and "Detective" issues for $1 million each, and higher.
"I've dealt with a lot of -- let's say, interesting well known people over the years," Fishler says, "so there's a whole gamut of collectors around the world who buy comic books."
The reasons for collecting, and at times, spending a fortune on a single issue, also run the gamut.
"There are people who maybe don't feel comfortable in traditional investments, or want to put it into something concrete," he explains. "There are people who are big fans, and now that they're an adult they want to capture some of that nostalgia. Comic books are a natural extension of wanting to collect and possess. There's a whole variety of motivations."
Headlines about seven-figure, record-breaking sales of a single comic book have increased interest in Fishler's business.
"We get calls from people around the country who either have collected these over the years or they might be in a situation where they stumbled across them in some way, and they're trying to find out what the value might be, and they rely on us for an expert opinion, and they talk about the possibility of selling what they have," he says.
A 10-point grading system for comics, accepted by the industry as a whole, is a recent phenomenon invented by Fishler.
"We give them the history from the past, or what the demand is right now or at least the ballpark estimate. Because of that grade, we can demand a value."
The economic downturn of recent years has pushed some treasures out of hiding.
"There was a family facing foreclosure and they found 'Action Comics' No. 1 in the house," Fishler says. "They had to empty the house, and found it in the basement. They didn't know where it came from but thought it could be a lot of money. We sold it for $436,000."
"For every call like that we get 25 calls with people saying they have something great and they don't."
A recent episode of "Hollywood Treasure" featured Lauren Vogt, an animator with a background in working on Tim Burton's stop-motion animated films, who called Maddalena when she lost her job. Maddalena began hunting her property for treasure, locating artifacts from the films "Nightmare Before Christmas" and "James and the Giant Peach" in a shed in her backyard.
While Fishler doesn't believe stories like these are typical when it comes to comic books, Maddalena has the opposite view about valuable items from Hollywood's past.
"Ask around, you may have friends who work in the industry, writers, directors, set decorators. You may have a friend who has a great box of scripts of 'I Love Lucy.' It's out there," he says. "You have to remember there's a couple of hundred people involved in these productions. There's tons of this out there."
Maddalena says this is just the beginning for Hollywood memorabilia collecting: "With rare movie memorabilia or television artifacts, you may have something in the basement, maybe your grandfather who was a cinematographer had. But people really still don't understand its value. So it's just started to catch people's attention. We're really in the beginning stages of this."
Whether they appeal to the film geek or the comic book geek, the passion for these items is what drives prices sky high. As Maddalena puts it, "They transport you back to a time period, an emotion, a sense. That's what collecting is all about no matter what you collect."
Tell us about what you collect in the comment area below.