Rakeback help needed partypoker/stars (I am a high volume player)

I have read through many messages on this forumn but have not been able to find decisive answers to my questions.

Right now I play over 1000 sit and go's on Pokerstars per month (mix of 50+5 and 100+9) and get exactly 0 rakeback or free money.

I plan on making my first deposit onto Party Poker within a couple of days. There I will test the waters and if I like it will be playing over 1000 sit and go's per month hopefully all 100 buyin (1 problem at stars is the 100's fill too slow).

What is my best approach to take to get rakeback or free money on either on of these sites for my high volume play? What kind of rakeback could I expect to get if I were to take this approach and ended up playing on average 1000 100 dollar sit and go's per month?

Thank you very much for your help,
Peter