Kenric - I found this campground in a campground book, and I tent camped there in July 2003.
Lost Lake is a very quiet and beautiful campground. There are not many sites, and they cannot be reserved. However, the sites are spaced apart very well, and the lake and mountain views are incredible. Around the lake there are many hiking and biking trails, which lead to a small waterfall on the other side of the lake. The downside is that this campground is 12 miles west of Crested Butte including 2 miles on a small dirt road.