I'm also interested in experiencing the many different varieties of Basil. Previously, I've only grown imported Italian basil (which I love) but this year I've started flats of several different varieties.
Botanical Interests sells a sampler packet containing seven different varieties of basil. The
Custom Blend includes Lemon Basil, Anise Basil, Cinnamon Basil, Purple Ruffles Basil, Dark Opal Basil, Thai Basil, and Genovese Basil. This
Custom Blend is available from
http://www.gardentrails.com for $1.89 (free delivery and no minimum order). This is an inexpensive way to get acquainted with several different basils.
I planted a test flat of seed (Italian Pesto Basil from
www.reneesgarden.com) left over from last year to see how viable it was. Nearly all the seeds germinated and are thriving! I guess the "packed for year" date isn't like an expiration date on a carton of milk, so you really don't have to spend money on new seeds every year.
I also harvested seed collected from last year's crop. I planted a test flat and those seeds have germinated and are also doing well. This seed was from a single variety planted together. I wonder what kind of varieties will be created from the cross-pollination my multi-variety crop this year?

Happy gardening and pizza making!
Regards,
David