The Squier 51 definitely has to rank as one of the great deals in guitar....but since your budget is a little higher, I'll throw my .02 in with a new addition to the ranks....if you're near a Guitar Center, take a look at the Schecter Gryphon ($399, so it's right at the top edge of your budget). It's a model made exclusively for GC, has twin humbucking pups that can also be split (by pulling up on the tone knob), so you can get either single-coil or humbucker sounds out of it. They're made in Korea, but setup here in America at their Burbank (CA) factory.
The reason I discovered this gem is that I just brought one home less than an hour ago.
The quality of the components is better than my MIM Fender Strat, and it plays like an absolute dream!