cheap guitars don't have to be bad, if newbies get frustrated just because the guitar is cheap and doesn't have that 'awesome' sound then they don't deserve to be playing guitar, yes you will get frustrated and if you want to blame the guitar be my guest but it won't make you get any better

like previous replies, all the things you have to look out for, plus don't be tempted by fancy stuff like a floyd rose bridge, keep it simple, I just remembered I didn't learn on a electric guitar at first, I had a crappy acoustic that belonged to my mother which had to be at least 30 years old, good enough for me though :D