I just picked up a plethora of Heirloom Carrot Seeds at the Seedy Saturday Symposium this past weekend. The varieties that I bought were: Scarlet Nantes, Purple Dragon, Nutri Red, St. Valerie (pink) and Amsterdam gold (yellow). I also bought another purple variety whose seed packet is currently eluding me. Anyway, you can buy the above listed varieties from:
or you can email them at:
Also, thought that I should mention that Carrots were originally purple and that they have been bread over many generations to be what we normally think of as a Carrot. The orange varieties do have a higher sugar content than the purple varieties though.