When do I start my seeds indoors? Johnny's Seeds has a great interactive seed starting guide. You enter your last frost date and the table tells when to start a large variety of vegetable and flower seeds indoors for Spring planting. Great tool!
Another Seed Starting Calculator. For this one just enter your ZIP code. I love Johnny's website and their resources. They have tons of information for folks trying to make a living out of large scale gardening or smallish farms. Lots of it is helpful for someone that wants to garden successfully.