For broadness of scope, it's hard to beat the NatureMapping Program, started in Washington State in 1992. The idea is to look everywhere and get a general picture. The Website also contains data-reporting forms, guidance manuals, and other useful information. Training sessions are available but not required. Participants send their reports to the NatureMapping central office at the University of Washington, where the volunteers' observations are laid over existing maps showing scientists' models for each animal's range.
People can look in different ways as long as they report in a consistent fashion.
Standardized data reporting is critical for accurate maps. To date, participants have reported 160,000 observations. As would be expected from the way the program is structured, most of the observations are of common species-and that's the idea. Yet these can have significant impacts on urban environments. People are telling us what's going on in their backyards, in cities and in sprawl areas.