There are the steps on merge. Pokerowned freerolls. Freerolls on almost every poker client. Bovada/Bodog used to give you a free $10 when you signed up if you were a new player. Not sure if this is still happening.
There are also sites like this Pokerspace.com - Poker Forum, Community and much more! that use a site currency similar to poker owned points. I've been a member of this site for years and been able to get about $50 free through different promotions. You can earn the sites points through various avenues. You can basically build a site points BR and use it for various tournaments then cash it in for money on select sites. The tournies are small so your odds are pretty good. It's a pretty good place and tourney competition varies if that's what you are looking for.