I have been doing the same thing acky. Bodog so far is the best site I can recommended, they have two 500$ freerolls everyday, anywhere from 3500 too 4500 are in and top 63 get paid. The also have freerolls where if you have a certain amount of pnts you can play, a lot less people get in those and you can build up pnts by just playing freerolls.
Sportsbook and Carbon Poker
are pretty good for freerolls as well, they offer some 200$ freerolls here and there, Sportsbook has 3 NL holdem 200$ freerolls daily, Carbon Poker has HORSE 200$ freerolls, Omaha 200$ freerolls, Razz 200$ freerolls, and of of course Holdem...I think though that only Holdem and Horse is daily on there.