Both are solid machines, both in build and function.
E330 is a newer model, 0.5 mgpix less, has live view + articulated LCD.Useful for macro, odd angles, stealth.
E300 has the solid kodak ccd which some prefer for its colour(subjective).
For $700 you could get the E300 easily 2nd hand from the Buy & Sell.
For me I would get the E330. You could do so much more with it. You could get one 2nd hand for a little more than your budget or bump it up a few hundred bucks and order it off the net. Firesale now for the E330 on some US online stores.