You play limit holdem?

There were some sights like Sportingbet and Total poker that had pretty easy $100 bonus for new players. I think it took 300 raked hands.

Absolute Poker always has a bonus, but the limit games can be pretty rockish, and you need a $10 pot to get a point towards bonus.

Doylesroom is a very easy site and usually has a 25% or so bonus that should go quickly at .5/1.