Aidpage

http://singleparents.about.com/  Has alot of information covering all sorts of topics.

http://www.zerotothree.org/site/PageServer?pagename=par_parents&AddInterest=1148 is a great site for developmental questions and resources.

Parents Without Partners is another resource site for single parents http://www.pwphouston.org/05singleparentsites.htm

Kids-In-Crisis is answers for kids and teens http://www.geocities.com/Heartland/Bluffs/5400/

Boys Town Hotline Information http://www.parenting.org/hotline/index.asp

I'll add more as I come across them. I would love to see more if you know of any.