There is a $4000 Online Slots Tournament running now through the end of May 2013 at Miami Club Casino. Entries and rebuys are just $1 on their newest online slot machine, High Roller.
To play, sign up and register at Miami Club Casino. Then. from the lobby, go to Tournaments and click on the online slots tournament named Spring Round Cash 2.
As of right now, the top prize is $600, with the top 9 finishers winning real cash. A further 350 will win at least $10 in bonus cash.
Miami Club Casino is US-friendly and accepts real-money players from all US states.