That all depends on where you are located and what kind of game you are looking for.
They have free 'league based' games throughout the Hampton Roads area during the week. Go to ACES Places
for a listing of all of the locations they play. There is no real requirements to join the league (like I said its all free) but they do ask that you show your patronage to the bar(s) that are hosting the regular games.
If you are looking for the 'home based' games (i.e. legal home games) then your best bet would be to start with these free tourneys and meet some people there. I used to host home games for a short period of time, but not having regulars that I knew it started to get sketchy.