I've been watching Ebay for Stuart Davis art. These things show up from time to time with a disclaimer saying they have no paperwork so they're being sold "in the manner of" Stuart Davis.
Ok... the art looks like Stuart Davis and the signature looks like Stuart Davis, but we can't promise you he painted this piece. Well, if this really was an original Stuart Davis piece it would be worth as much as $250K. Seems like if there's a snowball's chance that it is real it would be worth it to the seller to find out.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7324244019