Okay, well if you are starting out I wouldn't look at "the best" diving computer on the market - as that will set you back thousands of dollars and will have features that you'll probably not use (if ever) for years.
My recommendation would be to go for the
Suunto Vyper 2. It's currently got 19% off on Amazon and does everything you'll ever need.
Namely, it's got a nice big screen, so no squinting when you're underwater, an electronic compass and it works with nitrox - which will probably be your next step on the diving ladder.
Highly recommended, it's bargain reduced to $499 from $615. How does that fit in with your price range?