I'm a happy Yamaha digital piano owner (though if I had the money and the space, I'd buy a real Yamaha grand - used to have a G3, which I loved). Anyway, I own an old P-60, which you ought o be able to buy used somewhere for $300. It has weighted-key grand action and extreme touch sensitivity such that I don't miss not having a soft pedal with it.
Others who worry you'll get some sort of bad habits from play on digitals must not have tried the Yamahas. (Much better to play a weighted-key digital than a crappy, beat-up upright... or no piano at all!) What jimbo320 said is cool, about getting a P-95, which are upgrades from mine, but I'm mentioning the older digital P-60 because I think you'll be more likely to find a cheap one.
Plus, you not only get two wonderful-sounding grand-sampled sounds, but also two electric-piano sounds, two harpsichords, organs and a couple of weird ones I use very infrequently (99% of the time, it's set on Grand1). Good Luck!
Bruce