Since the PS3 decodes all the HD audio, pretty much any HDMI receiver that you can find will do as long as it accepts audio over HDMI. A lot of the cheaper/early HDMI receivers don't take audio, so make sure it doesn't say "passthrough."
For that budget you have many solid options on ebay or as refurb. I got a Denon 2307ci for $200 off ebay, it does everything you need. Some options:
Denon AVR 2307ci (or 887, same thing)
Denon AVR 1908 (or 788) on closeout at Fry's/Circuit City
Onkyo TX-SR674
Onkyo TX-SR605
Yamaha RX-V463 or even a RX-V663
Harman Kardon AVR-247 (from the Harman store on ebay)
and many more. Pretty much any 1 or 2 year-old HDMI receiver, or a lower-end new model at an open box / refurb deal will do the trick.
Do some google searches on the models I listed, read up on their pros/cons, read reviews (both professional and user reviews on sites like Amazon) browse some of the forum threads on them to learn what people say, and most of all educate yourself on the new audio formats and HDMI capabilities to understand if the receiver you buy will do what you need. It's really worth spending a few hours of your life over the next couple of weeks educating yourself; you should easily be able to find what you need within your budget and you'll have a better chance of being happy with what you get.