Herb Seedlings
Grow herbs from seeds.

Johnny Seeds
Seeds of Change
Heirloom Seeds

For plants I go to the local nursery,
but don't expect to find anything
other than the most common of herbs there.

For pest control and other stuff for gardening.
Gardens Alive

Organic Gardening magazine
idusty88
[The Witch's Garden]

Great Site for Growing Herbs at Home
Eriess
[Culpepers Apprentice]

06052001
Legionnaires'
Disease Associated with Potting Soil

The window box gardening post
(at the club) brought this to mind.
Though these items are a bit old,
it's well worth paying attention to this issue.