Cheapest priced copy (Gatecrash): $0.39 at Card Kingdom, near mint, their price list as of .
Undercity Informer 
Creature — Human Rogue · 2/3 · Uncommon · The List · #GTC-82
{1}, Sacrifice a creature: Target player reveals cards from the top of their library until they reveal a land card, then puts those cards into their graveyard.
Legal inCommanderModernVintage
Banned inPioneerLegacy
Not legal inBrawlStandardPauper
2 printings · $0.39 to $6.99 at Card Kingdom
One ruling from Wizards of the Coast
- 24 January 2013If the target player has no land cards in their library, all cards from that library will be revealed and put into their graveyard.