It depends on what kind of sound you're looking for, it's not simply as clear cut as what's good and what isn't. If you play at all, just find a Guitar Center or something and start testing guitars in your price range. Try whatever strikes your fancy and see if it's a fit for you.
If you want something for ripping out heavy rock and metal, check out Jackson, ESP, B.C. Rich and stuff along those lines, but if you want something more versatile to cover more styles, check out Fender and Gibson. Gibson is probably a good place to start anyway, and Epiphone (which is made by Gibson) has plenty of cheaper versions of Gibson guitars that are usually still pretty good quality.
If you want my advice down to a specific guitar, maybe try out a Gibson/Epiphone Les Paul. They cover a wide variety of styles, just like most Gibsons and Fenders, but they're also one of the most popular guitars on the planet, and so many other guitars are based off that one it's not even funny. For style, sound and playability, you can't really go wrong with a Les Paul.