Charitable write off?

I am big into donating to charities, but since things are little tight this year I was going to use them as a write off so I can pay off bills and thus be able to donate a larger chunk this year. I have all the slips to places I donated, but I can't find where I need to go or call to get the financial report to be able to claim them. Any help? Would I call the "pledge questions" number or can I request a copy online?