Helpful Links:
The NAF
Useful if you're interested in paying a $10 member's fee. Right now they're really behind the curve, so I actually wouldn't recommend you pay yet until they get more organized.
FUMBBL: Online BB League
Great Java application that allows you to play online against other people for free. After you sign up, hit the "Help" button to some great team strategies and tactics.
Talk Blood Bowl Forums
Best english Blood Bowl resource available. It takes about a week to sign up, but it's worth it. Easily the best place to find help or anything Blood Bowl related.
Midgaurd blood Bowl
Another great resource for strategy and tactics. A little dated, but most of the info still applies.
Good luck, Coaches!