If you haven't spoken with your school's financial aid department about this issue, I'd start there.
Also, some people in doctoral programs look to teach undergraduate courses as an adjunct as a way to make some money to cover their tuition. There are only so many hours in a day, though so it's a solution that doesn't work for everyone.
When it comes to grants, as an online doctoral student myself I can tell you that there aren't that many scholarships out there for people like us, but there are more than zero either. Why not check out our scholarship search just in case there's something for which you're qualified?
http://www.elearners.com/scholarships/
Good luck,
-=Steve=-
B.S., Info Sys, Charter Oak State College
M.A., Educational Tech Leadership, George Washington University
Doctor of Health Education, A.T. Still University, in progress