[AnthonyG]

I play a lot more outdoors than I have indoors. I started with a plate carrier, and am now switching to a chest rig because it is lighter and better for wooded environments where the extra "padding" of a plate carrier really isn't necessary. Something like a condor recon chest rig makes an excellent starter rig; but like others have said you don't need any of this fancy gear to play your first game.

If I was starting again I would probably invest in a good set of pants as one of my first items. You should be able to find a $25 pair of used military surplus pants that will have pockets large enough to carry m4-sized magazines. Some of the newer (better-designed) pants made by Propper or Tru-spec would be a bit more expensive, but will come with extras like lower-leg pockets, reinforced knees or integrated knee pads.

I would second the battle belt idea. You will maintain much more maneuverability as opposed to a full plate carrier, which you can always add later.
Go play a game, see what other people are using.