Hi,
Welcome to the AA forums and the world of Airsoft/Milsim. I started playing about 2 years ago, and love it! If you go milsim events or even your local fields, you'll meet a great group of guys and a few gals. I'm former USAF, I missed the camaraderie of being with the fella's and this game has really helped me out.
I would suggest the following gear and guns. This is just my opinion.
Try to go a with a full metal body gun. Some good brands are KWA and VFC. G&G also makes some good full metal guns.
To keep the cost down go with Condor on a plate carrier or chest rig to carry your mags, gear, etc. There are a ton of other brands, the sky is the limit.
Camo: any type. Most guys have at least ACU, woodland M81, DCU, etc. Most milsim games have tan or green teams. So try to get a set of both colors.
Youtube can be your friend. Just type in airsoft or milsim loadouts and you'll be set for the weekend.
I also have a website showcasing my gear reviews and game play.
http://www.jimmermilsim.com/Again, welcome to the world of airsoft/ milsim.