Hi- I am a really big fan of Johnny's Selected Seed, which is based out of Maine, and so has a lot of short season variates. Johnny's also does their own breeding, and carries quit a few items that they have bred. Probably a third of their variates are organic, and they carry a lot of heirloom tomato variates, as well as other heirlooms. One of my favorites that is a Johnny's exclusive is Hakurei Japanese turnips. These are by far my favorite turnips, and a lot of posters on Gardenweb love them too.
Johnny's also has fantastic customer service. The one time I ordered seed potato from them, my order never came, and I am sure the post office lost the order. I called up Johnny's and they told me they shipped out the order two weeks before, and I should have gotten it, but they sent me another bag of seed potatoes for free, even though I am sure it was not their fault. In our condo building, we had been dealing with substitute mailmen every day for at least a couple of months, and we had many problems with stuff not being delivered.
The only thing I don't order from Johnny's is seed potato, but I order everything else from them, and I have been really happy with them.
http://www.johnnyseeds.com/default.aspxHope this helps, Nancy