Well, a few... Just go to your local library and take out some books on Comic Drawing. Not how I started, but some good techniques.
Of course you can find many tutorials on the net or in your local library.
But none will work without constant practice. Also, the best tutorial you can find is to go out, and draw what you see.
^^
Yeh, if you want to get as good as Swisslad here, or even if you DARE to try and be as amazingly fantastic as myself ( 
), just practice. A lot.
Then go out, and do it again.
I've seen several comic style drawings on the boards. Now I like to know, how did you all learn this? Are there any good tutorials on internet?