Not all clans are rude, the same can be said for the players themselves.
But finding a clan that says they will train, and that actually will, is another thing.
Most from what I have seen, want those elite gamers, that will make a name for their clan.
I would say, make friends in the games first, and look for a clan later, if that is what you are after.
If you are after general training, these forums can be very helpfull, never be afraid to ask questions.
If you want, my friends and I would be more than willing to help where we can.
We aren't a clan, just friends that get together, I am on most every night, game name ........
Crookedfoot
((Not knowing your knowledge on Bnet commands))
/whois Crookedfoot
will tell you if I am on Bnet, and where
/msg Crookedfoot ( and a message )
will send a whisper to me
Or, I think you can send personal messages through these forums too.
Good luck, and good gaming,