mbgold,
you can definitely use an acoustic to learn, but it will be so much more fun to use an electric! Not only that, but many of the things you'll learn in the rock course are about tone and getting that crunchy sound from your guiatar. So using an acoustic will not be good for learning to obtain that tone, palm muting, pinch harmonics, etc..
If you're looking for the best electric guitar for less than $500, I would high recommend a MIM (made in Mexico) Fender Stratocaster. It's made in Mexico, but it's at Fender's actual factory in Mexico. It's not like it's a cheap knock off at all. Many experienced players buy a MIM and simply switch the pickups (not that the stock pickups are even bad) out. And I'll take that over an American made with stock pickups any day. But that's just me.
PRS is another good option, but try it out first and make sure you like the feel of it.
But if you're a Les Paul man, Gibson Les Pauls are gonna run you at least $2,000 (brand new). And keep in mind that Les Pauls have skinnier frets, not leaving as much room to play especially on the higher notes. Epiphone has a really cheap version and they're not bad for the price, but they're not good either.
And another great option would be an Ibanez. You can get an amazing Ibanez for around $700 and their craftsmanship is second to none.
But above all, try all these guitars out for a while. And don't just buy something because it's the only kind in Guitar Center. You can have them order ANYTHING you want in pretty much any color. And I would definitely go through them if you're ordering new, because they have a 30 day policy where you can return the guitar for a full refund for any reason at all. So this will give you a month to make sure you like it.
