I found a site that has a list of DI schools with message boards. Some of the larger schools with multiple message boards don't have them all listed, and some of the links are broken or wrong, Sam Houston for example, but it's a good place to start when looking for an opponents website. Like this Sunday evening. Thankfully, hostile and abusive websites and schools are not listed.
I'm still searching for the Denver board, there are a couple out there, but look like they've been abandoned. Funny thing I found, UMKC has an active fan board, who knew?
There's a whole lotta other stuff on there as well.
http://collegesportsinfo.com/directory/