Sources

If we look at charaties and nonprofits as businesses, which they are, a great website to get background financial information is the Securities Exchange Commission.  The SEC requires companies to file certain documents that are readily available to the public.  If you are researching a non-profit, a company's 990 is especially important to look into that way you can compare the administrative costs and the amount that actually goes into the charitable fund.  The SEC website is a great jumping off point when profiling businesses.
http://www.sec.gov/

Another way to start profiling a business would be to search it on the Department of State website.  This is Pennsylvania's business search..
https://www.corporations.state.pa.us/corp/soskb/csearch.asp