Department of Natural Resources for each state:

Of the states I reviewed each one has it's own DNR page. If you type in the following address and in the "yourstate" area type in your states abb. then you will find your states site. In Ohio's site it has a great page on Ohio animals a to z. I can't say for sure if your state will have that as well, but it is worth checking out.
http://www.dnr.state.yourstate.us

United States Fauna for animals

http://www.unitedstatesfauna.com/

Endangered American Animals

http://www.animalinfo.org/country/usa.htm

Illinios Habitats, but can be used for general reference


http://dnr.state.il.us/orep/c2000/guide/habitats/grasslands/definition.htm

Have fun building an online habitat at Switchzoo


http://www.switcheroozoo.com/games/habitatgame.htm