I would think your local feed store. Make sure it's unmedicated starter. Personally I just use oatmeal. I get the big containers. One each of instant and the other kind. Took me half of each to start in my rubber tote. I have done well. In 1 month of getting my worms, I have eggs and a few teeny tiny worms. I put carrots and sliced potatoes, but the potatoes shouldn't be on the oats or such (mold). And I throw slices of bread in. The beetles love laying eggs on the bread. I now have thousands of baby worms and probably just as many eggs. It has been 1 1/2 months since receiving my 1200 worms.