I just went and checked out the previous poster's rec to the PTASecure site, and ouch! $40 per month + a $150 setup fee?!
Personally, we go through Dreamhost (
Web Hosting by DreamHost Web Hosting: Web Sites, Domain Registration, WordPress, Ruby on Rails, all on Debian Linux!
), who offers lifetime free service to non-profits with proof of 501(c)(3) status. It took us all of 2 days to get the set up with them done, and then my husband built the site himself. We did have to buy our own domain name, but with the hosting being free, that wasn't a huge deal to us. Then we contacted Google Apps For Education, also free, in order to use their services, and we use the PTO Today version of the Constant Contact program for free.
Who you go through is entirely your group's decision, but I just wanted to put my $0.02 in regarding paying $480 per year to get something that you can get for free from good, reputable hosting companies. None of the functionality offered by that site is difficult for anyone with a modicum of skill to build. Even if no one on your board has that skill (which it sounds like you do), it's almost certain that someone in your parent group does.