I will try to post some clips, (no recording equipment, only "garageband") so quality maybe dubious!
Well, hey, I've been finding GarageBand a pretty cheap and cheerful way to sketch out ideas. It's not as clever as Cubase or my ol' VS-1680, but it is a heck of a lot easier (and prettier :)) to use.
Are you using Apple's amp sims or something like a POD? I've been futzing around with the built-in GarageBand amp sims (pretty minimal! but, again, easy to dial up), though I've sometimes used my ol' SansAMP GT-2, and have been thinking about a Toneport/Gearbox thingy from Line6 (which would pretty much make my reasonably new Tascam US-122 obsolete, but hey ....).
(Sorry to have pretended to hijack the thread -- this post really belongs in Tech, I guess!)