Not sure I have earned a place to say welcome as this is also my first post, but to attempt an answer at your question. What to expect? You can expect to meet a ton of great people who like to have a good time. There will be some who are pretty serious about the sport, but overall, just regular Joes out doing what they love, shooting bows.
Tips and Tricks. The best tip you can get is the age old practice, practice, practice. However, what you really will need to concentrate on is judging yardage. In the "old days" (15-20 years ago) if you could judge yardage within 3-4 yards you'd fair pretty well at a shoot. Now days, with ASA targets and such, if you are looking to climb the ranks you have to be pretty much spot on with your judgement.