If you are looking for some inexpensive seeds I found some at my local Dollar Tree - 10 for $1. I got lots of vegetable seeds (cauliflower, zuchini, lettuce, 2 types of radishes and carrots, beets, dill, chives, and a few flowers). Rite-Aid also has seeds that are 5 for $1. Of course the cheapest seeds are the free ones you save from your own plants.
Another amazing place is Seeds of Change (http://www.seedsofchange.com). Their website says they have over 600 distinct varieties of 100% organically grown seeds and I love looking at their print catalog. Our natural health coop food store sells them as well.
We now have about 150 little tomato seedlings so I guess I better plant some other vegetables :)