The PS3, Wii and 360 bundles will set you back $US 189.99. The PS2 bundle is 10 bones less, $US 179.99. Presumably these all include the game, guitar, drums and a mike. Gamestop just put the info up on its website, and Gaming Bits caught the scoop, noting that the bundle is $US 20 more than the Rock Band Special Edition bundle.
If you want to buy just the guitar and the game, you can get those for $US 99.99 and $US 59.99/$US 49.99 respectively. The release date is Oct. 27, 2008.
Guitar Hero: World Tour Priced at Gamestop [Gaming Bits]