Recommend me a PSU

Hello all, I'm slowly building my first computer, and it's nearing completion now. However, I just don't know what to get for a PSU. I don't need anything crazy just something that'll run the hardware I have reliably. The parts I have are.....

MoBo

RAM

Case (Shouldn't really matter but ya never know, this case makes me put the PSU in upside down)

CPU

And For the graphics card I plan on tossing a ATI Radeon 4850 or 4890 in there. So if any experienced PC builders can lend a hand and reccomend something they've had success with I'd appreciate it. Thanks alot!

Edit: Also Im gonna use windows 7 64 bit home premium. And also if anybody could reccomend a decent 250-320 gig HDD I'd be grateful too. Thanks alot!