Helping Out the Local Animal Shelters/Pounds

I am hoping to be able to collect some donations for a great cause, the cats and dogs of my local animal shelters. I live in the Columbus, Ohio area, and have noticed over-crowding in many of the shelters, with many animals coming to them in terrible condition. They need veterinarian attention for everything from dental care, skin issues, eye care and their basic shots and worming. Help with food costs is also greatly appreciated by these shelters. I've noticed the issue, but unfortunately am not able to make any substantial contributions due to my financial situation. I am very willing to donate my time, however, in making sure these animals and the kind volunteers of these shelters get help. Any donation would be greatly appreciated.