All of these sites include images of spring peepers, and many have recordings of their song.
Northern Spring Peeper
Rhode Island Vernal Pools, University of RI Dept. of Natural Resources Science.
Southern Spring Peeper
Florida Wildlife Extension, Dept. Of Wildlife Biology and Conservation.
Institute of Food and Agricultural Sciences at the University of Florida.
Animal Diversity Web, University of Michigan Museum of Geology.
AmphibiaWeb, in conjunction with the Digital Library Project, U.C., Berkeley.
Search for "spring peeper" under vernacular name.
The Center for North American Herpetology.
Spring Peeper, Pseudacris crucifer
Northern Prairie Wildlife Research Center, USGS.
Wildlife Diversity Section, Indiana Department of Natural Resources.
Compiled by Allison P. Kelly, March, 2005