I think Poker Stars is a good first site. It doesn't offer rakeback but I think you can take advantage of s first time deposit bonus, check out
www.bonuswhores.com. I'd play at Pokerstars until I could fully take advantage of bonuses and rakeback at other sites.
I would recommend you invested in Poker Tacker and PokerAceHUD. RealtimeHUD is a good (free) alternative to PokerAceHUD at Stars (free - see
www.holdemranger.com).
To get rakeback who usually sign up at a site using affiliate The affiliate credits your poker account each month with a portion (usually around 30%) of the rake you play. There are two sponsored forums here that you can get more details from.
EDIT (bobbyi): Link to example affiliate removed. Forum policy prohibits affiliate links because they tend to promote spam (not to imply that you were spamming). Thanks.