Ann Klucsarits, director of development at The Heritage Foundation, lays out some guidelines for getting funds in 10 Steps to Persuasive Proposals. You'd be surprised how little things can make a difference:
A few years ago, The Heritage Foundation received a grant from a foundation, and the gift was much larger than we had expected. When we called to thank the program officer, we asked why the foundation had increased its support. It was not because our project was deemed more effective or that our proposal was more persuasive. The reason was simply that we had turned our proposal in on time, complete with all the attachments, and many other requestors had not. So, in the end, the foundation rejected a number of proposals and had more money to give to fewer organizations—and we benefited.
There's a little more to it than that of course, but getting the easy stuff right always improves your chances. For more on fundraising, check out this feature by The Heritage Foundation's John Von Kannon.
Both writers suggest a few helpful Web sites:
A subscription to the Chronicle of Philanthropy, which often summarizes grant guidelines and areas of interest for different foundations.