They have never called me from the Heritage Foundation, do you have to be on their list in order for them to call you? I would donate to them and I would donate to Vets groups as well, like Wounded Warriors I see the commercials all the time
http://www.charitynavigator.org/
The above site has all the info on the various organizations. I gave to Wounded Warriors once. Have heard some not nice things about it though - but not sure how true they are.
I used to give to Prison Fellowship (Angel Tree), but over the years they have gotten pretty top heavy with less and less going to the actual services.
We give to three things locally that we can help out with too and keeps us in touch with things.