Mac noob here, too. I've been using Diablo with some success. Get it here:
http://bitcointalk.org/index.php?topic=1721.0

Works with deepbit.net. But it dies all of the time. I'm not sure if it's the app or the pool because all of my Mac's Diablo instances die at the same time. Bitcoin-miner.exe on my thinkpad doesn't die.

Still tweaking...

Goodluck.