One place, if you have the time or interest, is to look at the Non-Profits form 990. These are required to be filed yearly and provide a great deal of detail on some interesting elements like salaries of key people.
One place to look at this information is on the National Center for Charitable Statistics.
Here is their website nccsweb.urban.org
I always ask the person that calls from the firefighters or police associations what it is like to be a cop or a firefighter. More often than not, the person on the other line either hangs up or explains timidly that they are "working on behalf of" those organizations.
I do always win a bid at the Operation Muskie auction emceed by John Gillespie every year at the Musky Expo. Hopefully it will still be taking place at the new location.
That, and the red kettles is about it for me...and Girl Scout cookies!
What I am referring to is this: Telemarketer calls and you donate $100.00, only $15.00 of that hits the bank. The rest has to cover the expenses of the telemarketing agency and other misc. overhead.
We got absolutely hammered by Channel 4 back in '08 on this topic when we were hosting the National Veterans Wheelchair Games. Had to hand it to them for the timing of the story. Painted the WPVA as thieves. WAYYY too 1 sided.