My first question would be are all my old codex's and rule book out of date?
Second is the game fairly balanced? I mean I know there are points and stuff, but does any army dominate the tournament scene? I always thought space marines were really over powered, but I was pretty naive last time I played lol.
Then is there a website or message board for finding players, tournaments or just general strategy? The few guys at the hobby shop near my house think they are better than the world and aren't really cool to talk to.
First off, probably almost all of your old codexes are no longer tournament legal. Since you last played in 3rd edition, the only codexes that are still valid are the following:
Every Other codex and the rulebook has been updated since. mostly for the best with a few exceptions.
Secondly, in the new edition, things are very well balanced AGAINST EACH OTHER, which is to say that the 5th Edition Codexes may seem a bit overpowered against the 4th edition codexes because of GW's push to have more models in your army. The 5th edition codexes include:
There are those who say that there are more, but they are wrong. the others are 4th edition codexes and while some are still very powerful (Tau, Dark Eldar, Witch Hunters, Eldar) for the most part they do not stand up to the viability of those 4 codexes.
And lastly there are a lot of places around the web that offer lots of advice.
It really depends on the army you play though. as far as a "Game Finder" service I know that there are some out there, but I've had absoloutely no luck using them. It could be because I'm from a backwater area, but more of a possibility is that nobody uses them and just goes to their local shop to find a game.
Keep at it and if you have any more questions, be sure to let me know. I'll answer them as best I am able.