The first is Camp Out Colorado, a very complete guide to enjoying the outdoors of that beautiful state. You can find a campsite, pick a good time of year, and even ask questions on their forum.
The other site I found is Hiking Northern Michigan, started and run by the husband-and-wife team of Adam and Rhonda Greene. Avid hiking and camping enthusiasts, they offer a trail guide, photos, videos, and a hiking blog on their website.
Those are just two great resources to help inspire you and help you plan your next outdoor adventure. I'll share more sites as I find them.