Fake fossils from China have saturated the NYC market, some found in Chinatown and then other very suspicious-looking fossils of extremely rare species in spectacular condition, seeping into more upscale gem stores. I think they will eventually get to ebay if they are not already among us.  Here are examples of some obvious fakes.

"Perfect Fish Fossils" with details simply painted on.  These are very difficult to detect without actually scraping the specimen but generally if its just too perfect, then don't buy it. The painting of poor quality fish fossils are currently big business.

"Undiscovered Species" at bargain prices:  You will see tiny plesiosaurs with all sorts of appendages, fins, arms, hands, pterosaur-tails, things which you will find in no book, which are nothing more than a fossil fragment with more paintings and attachments. Beware the "undiscovered plesiosaur!"

"The glued together Chimera":  Take one half of a plesiosaur fossil and the other half a fish fossil and see how they are glued together for another "undiscovered species." 

"The Crude negative casting": This is simply a piece of high strength ceramic, dyed the appropriate color (tans are popular) where a extant scorpion or insect has been pushed into it. Wallah! Instant Fossil.

Fossil Shrimp:  Chinese fossil shrimp are coming to the US in abundance. Yes, it may have been a real fossil shrimp but again, antennae and all sorts of appendages have been painted on in the appropriate colors.  If its too good to be true, pass it by.

Ice Age Animal Parts:  Here you will see an abundance of horse teeth, cow teeth, deer teeth which have simply been dyed black or blue or really worked over on somebody's grinding wheel.  The stuff is modern, some of it is no more imaginative than a deer mandible which has been soaking in black tea for a week.

Let the Buyer Beware when looking at "Chinese" fossils.  ML/Brooklyn, NY