This will COMPLETELY depend on WHICH Wagner card you're referring to. For example, the most valuable and rare (possibly) card in rare baseball card existance is the 1909-1911 T-206 tobacco card of...
Auction Block.
The high profile T206 Honus Wagner card occasionally come up for auction. When it does, The news of the up coming sale is advertised Internet wide or in trade papers. Recent auctions...
Fake and Reprint.
A "Fake" Honus Wagner T206 baseball card will have no collectors value, and would be a crime to sell it as such. An authorized reprint of the T-206 Honus Wagner card (reprint...