I am no pro, or expert on cameras, in fact I shouldn't even be in this section since I have vowed to keep photography as a true "hobby" and not let myself get consumed. However about a year ago I picked up a Sony A55 for right around your budget. I'll admit I didn't do a lot of comparison shopping, so there may be better out there, but so far I have been more than happy with it.
The biggest pluses for me are:
The ability to do 10fps. With 10fps it makes it a bit easier for my amateur skills to catch the right moment in action shots. (racing is a big one for me, but sports of any kind count)
The ability to pick up fairly inexpensive lenses when the stock one doesn't quite do it for you anymore. The Sony line carried over the Minolta mount when they bought them out years ago. This means that you can browse craigslist for some older (but not too old) Minolta pieces that are still in good shape, but may not be super over priced.
You can see multiple examples of the quality that I can produce with it (good or bad) either here
http://mostdesigns.com/ or search my recent posts, I put a few photos up in the "off topic" area not too long ago from Toyotafest.
