American Alliance of Museums
American Alliance of Museums shares detailed salary information for executive directors, which is organized by museum type, region, geographic setting and budget size, plus individual characteristics (age, gender, academic preparation and time in position).
Charity Navigator provides data about CEO compensation in a 2012 survey. (PDF, 18 pages)
The Foundation Group shares a resource on considerations for reasonable nonprofit executive compensation.
Minnesota Council of Nonprofits
Minnesota Council of Nonprofits shares best practices on disclosure and procedure insight in establishing executive compensation.