Barack Obama s election is being hailed as a historic moment. Does that make buying a $100 copy of November 5th s Chicago Tribune on eBay, with an original cost of 75 cents, a good investment?

Memorabilia from the 2008 presidential election is popping up for sale everywhere, with merchants on eBay offering items ranging from a patch of grass from Grant Park (at one point showing a bid of one cent) to a $20,000 ( Buy it Now price) signed first-edition copy of Obama s book, Dreams From My Father. But collectible experts say only certain types of items are likely to hold or increase their value. Here s a guide to sizing up Obamabilia:

AUTOGRAPHS
For collectors, it is important that autographs be authenticated. Tom Carrier, an expert in presidential memorabilia who advises WorthPoint.com, an antiques and collectibles web site, says that anything with a date and place on it, such as a ticket or program from a campaign event, will normally be accepted as legitimate. But if prices on these items spike, so does the chance for fakes. The value of an autograph varies with what it is written on, and connoisseurs particularly covet clear, vibrant signatures on an easily readable background. A signed, limited edition Obama campaign poster recently sold for $2,800 on eBay, although Carrier thinks this price may subside along with the euphoria surrounding election night. A regular copy of an Obama book carrying his autograph will probably hover at around $200 to $400, says Carrier.

Be careful, though. Historically, purveyors of faked memorabilia have flourished online, where it's easier to maintain anonymity and keep buyers at arm's length from the actual product before they plunk down their cash. The best way to ensure you are buying the real deal is to purchase from a reputable dealer with deep authentication experience; experts say that you should approach every piece -- and, indeed, every certificate of authenticity -- with skepticism. Carrier says he has this golden rule: "If it was not signed in front of you, the autograph was not signed by that person." A trustworthy starting point for collectors seeking advice is the American Political Items Collectors at apic.us.

BUTTONS
Partisan buttons are turned out by the millions. But some can also turn into rare gems. The smaller the number produced of a given button, the more valuable they become. Also, buttons tied to key events can be more valuable. Jim Warlick, creator of the USA Button Poll, which predicts the outcome of presidential elections (accurately but not scientifically) based on the number of people buying certain buttons, and a presidential collector for 30 years, says that any button that was produced for Obama s Denver acceptance speech is worth holding onto, particularly since the event took place on the 45th anniversary of Martin Luther King telling the world, I have a dream. The value of a special button could double in a year, according to Warlick, who currently sells certain JFK pins for $75 a pop.

T-SHIRTS AND NEWSPAPERS
Clothing doesn t keep well -- and the McCain brand, in particular, may never bounce back. And newspapers, despite their iconic nature, are often too common. The New York Times printed an extra 50,000 copies of its Wednesday paper, and the Chicago Tribune an additional 200,000. A newspaper announcing victory for Dewey over Truman in 1948 recently sold for $7,000, but this year there was no surprise. They don t have great value, says Carrier. If you want to keep them for posterity, store in an acid-free environment.

INAUGURAL ITEMS
Experts expect inaugural gear will be hot this year. Inauguration day programs and other items, like tickets from inside the barriers, that can be tied to the Capitol on Jan. 20 will likely be most sought after. Police signs from the day of the JFK inauguration, picked up from the street for free, can sell today for $200, says Warlick. Meanwhile, Warlick, a third of whose collection once featured the Clinton cat, Socks, says he found a clue in Obama s election night speech as to the next rave :

[Obama] said he was buying a new puppy. When the pictures and the name of that puppy appear, that puppy will be on everything.