I pre-ordered mine, got it the day before it was released in stores for $79 Using the old crappy guitar though, the new ones are worth the money.
Have you tried buying separate? EB in Belco did me a deal with buying the game and guitar (GH2) separate for the same price as package because they had no bundles left (was christmas time last year so same thing your going through), think its about $20 more if you get them separate so not too much extra anyway.
Or you could do the better thing and just wait till next year and buy Rock Band, its like Guitar Hero but 4 times better because you can play 4 player mode with Guitar (guitar and bass guitar), drums (with drum kit) or vocal (microphone, same thing as singstar) http://en.wikipedia.org/wiki/Rock_Band_(video_game) Cant wait