Justin121: you can but at the cost of seeds, especially some of the feminized auto flowering variety, wouldn't you be, "penny wise and pound foolish?"
I got started on a Technaflora's, "Recipe for Success," sample starter kit a couple of years ago and I've never looked back. It was about $30 and it lasted me a long time in my Aerogardens. And that was without half the nutrient problems you read about these people having in the forums. I would at least investigate Technaflora. HSA