As suggested elsewhere, the best way for us to introduce people to 6v6 is to partner people up for one-on-one introductions. From there we can move on to team sessions and mixes as people are ready.
Here's what I'm looking for:
If you're interested in getting into 6v6 please post
one class from the standard four (Scout, Soldier, Demoman, Medic) that you wish to learn to start with. You can diversify later, but you'll find it much easier to just have a solid primary class to start with. I also need to be strict on the class selections, you're not going to find anyone willing to teach you competitive Engineer.

If you're interested in teaching, post which classes you are interested in mentoring for. Preferably played to at least a strong Div 5/6 level. I'm not asking for much, but some competency is necessary. Knowledge of tactics, positioning and explosive jumps (where relevant) more important than deathmatching skill.
I can either try and pair people up that I think would be suitable, or you can contact directly. From all I'm expecting this to be taken seriously. The priority is of course to have fun, but that won't happen without a little effort and commitment from both sides.

One final point I wish to add:
no-one is "not good enough" to learn. If the idea of 6v6 play appeals, get involved!
LearnersAllytk - Soldier/Demoman
Berath - Demoman
Hawker - Scout
Omni - Medic (/Soldier)
r007 - Medic
Sk1nn3d - Soldier/Medic
Terror - Demoman
MentorsBurnalot - Soldier, Scout
Chaos - Scout, Soldier, Demoman, Medic
Jebus - Soldier
Karthus - Medic, Soldier
Leftism - Medic, Demoman, Soldier
mode - Scout, Medic, Demoman
Power - Scout