Hi everybody!

I'm from spain, and I want to join an american server to be able to join american channels.

I have tried to find a server, but I don't know what to do

Can you help me?

Thanks a lot!

Try looking at SearchIRC.com

Join any of the top networks and most channels are likely to be "american", if by american, you mean they are in english.

Here are two networks...
irc.undernet.org
irc.efnet.net