For general feedback about the game.Steam Support
Visit the support site for any issues you may be having with the game or Steam.
The second six on six newbie mix cup is about to be begin with the special moniker, Christmas Cup. The rules are simple; its a double knockout tournament where teams are comprised of five individuals and one experienced mentor, who will then take part in a week long tournament with some great christmas prizes.
No prior TF2 experience is required, although they reccomend you take part in a few matches beforehand to get a feel for it. These can be joined via their Steam community. You can also seek out a mentor via the same source.
To sign up, or see additional rules, visit their Steam community group.