PokRok said:
What site would you sign up to?
Not sure for that amount of money. A site that offers a deposit bonus though, for sure.
Would you play for bonuses or just winnings?
Winnings. Bonus is exactly that: a bonus.
Would you play tournaments or cash tables?
The very lowest of microlimits; $50 is not really enough to withstand a downswing of any larger capacity (because there aren't many tournaments that have buy-ins low enough to give you enough shots).
If you sign up for a deposit bonus, by the way, make sure to read the Terms&Conditions so that the limits you intend to play actually give credit for clearing the bonus.
Here's my tip, though: Deposit the $50 into
pokerstars. You won't get a deposit bonus, but that's alright because the lowest limit tables aren't raked anyway. The upside is that you'll have great game selection, and you won't get raked, and they spread REALLY low limits.
Once you've built up ~$200 is when you can start to farm bonuses elsewhere and play something like $.25/$.50 limit (a lot lower if you plan on playing no-limit, but if you're just starting out I'd recommend learning limit first anyway).
Cheers,
FP