Don't know of anything in writing. Check out
http://pickleballcommunity.com which is the local community website. Pickleball 101 will probably be your best bet for how things are done in The Villages.
As a rule, beginners should avoid the open sessions from sunrise to 10 am. Watch the schedule published for each rec center to check the 10am-noon sessions, as many of them are specified to skill level, such as advanced beginner open (mixed) or intermediate men. Watch for other times in the schedules as times are often reserved for specific social groups.
Other than that, if going to an open session, get your place in line and head out to the next available court with a group of 4. If there are lines, play a game to 11 and then take your place to the back of the line.
And don't hesitate to ask questions of other who are there and get to know the people with you in line. You'll be surprised how friend and helpful most people are!