Seeing as this gathering is only a short 2.5 months away I'd thought I'd chime in to give you guys some links that I follow almost on a daily basis. Since you all will be in the area of 2 of the best parks in the country, Yellowstone & Grand Teton National Parks, (IMHO) there is a multitude of info about the parks out there. These links I consider are some of the best and most complete info to find any kind of info wether it would be campgrounds, geysers, scenic areas, animal sightings & the like.
#1
http://yellowstone.net/ YNET is what I consider the best, most up to date website on Yellowstone on the internet. Check out the forum section for great reads on what is happening in the park at any given time.
http://forums.yellowstone.net/index.php #2
http://www.yellowstone.co/ This site is also ran by a friend of mine, John Uhler. Deals mostly w/ Yellowstone but you'll also find some stuff on GTNP.
Bruce