posted 11-23-2009 03:01 PM
Unless an astronaut knows you personally, the chances of him/her sending you something flown is very low. Even if they do know you, today's astronauts are permitted to retain very few items so it is not as if they have a large supply from which to send.NASA doesn't operate a store for flown items but if they are surplussed as scrap, they can sometimes be obtained directly through GSA auctions and sales. In recent years, the agency has become rather savvy about the "eBay market" and so the chances of finding flown artifacts among the more mundane surplus, which can also be identified as such, is low.
As with all collectibles, if you are well read and know what you are doing, then it is possible to obtain authentic space shuttle artifacts on eBay and through other auctions (released through earlier GSA auctions, or in some rare instances, sold by recipients who were fortunate enough to receive a gift from an astronaut they know).
If you live outside the U.S., you may wish to limit your expectations to souvenirs that were flown onboard (such as flags) as many parts of the orbiters themselves are prohibited from legal export.