Wish I could find a search source for donors and their donations to various non-profits.
That info isn't mandated to be provided by the Non-profits, thus I doubt you'll find a source listing the donors.
Actually, it's part of the 990s that they have to file, and those 990s are part of public access. Guidestar.org provides the PDF files. You can pull up a particular "charity" like Planned Parenthood in a certain region, and see where their money comes from. They are supposed to provide a list of donors, but those donors are often foundation "fronts." Or you can see where a particularly charitable foundation disperses its own funds.
What I'd like is a cross-referenced spreadsheet.