You can find almost any freeroll available on the internet listed here.

Find a Poker freeroll site, signup with or without a deposit. Go to Tournments then freerolls.

You will find all tournaments listed here at your respective sites. Once you find the tournaments you want to play. Then, simply register and play. After you play a few try to win a few. All freeroll winnings can be used immediately for cash games or mtts. You will need to earn poker points to cashout freeroll winnings however. Poker points are earned by playing real money games.