Unless otherwise noted, each tournament you see will have the standard Am Divisions:
|MA1: Advanced||Am's rated 935 or higher must play this|
|MA2: Intermediate||must be < 935 rating|
|MA3: Recreational||must be < 900 rating|
|MA4: Novice||must be <850|
SO! Depending on if the tourney is PDGA sanctioned or not, the ratings can somewhat guide you into a specific division. Given your said experience, and if you're looking for a challenge, play Intermediate. Playing 'up' always has its advantages, such as getting to see people better than you, how they throw, handle the game, prepare etc etc. Playing 'down' also has its advantages too. for example, if you're the leader going into the final round you'll be taught how to preserve your lead, manage the course and win a tournament.
Both are great, and its always the best when you play up AND win.
There's a tournament this saturday, the DD Rosedale 1 rounder. I would suggest playing in that as its non-sanctioned and should be a great tourney for you to start in. Study your rule book, and prepare yourself mentally and physically (should be a hot one!)