I never would have guessed I’d have such a green thumb, but since I got into using home-grown herbs (both culinary and medicinal) last spring, it’s become a pretty lovable hobby. Right now I’m at home, and working on planting a bunch of things:
We’ve already got a very healthy crop of sage growing here, and a slightly-less-healthy-but-still-useful bit of rosemary (though I’m theorizing that if I move the rosemary to somewhere where it’ll get more sun, it’ll do better). I’ve been madly potting other things lately: Cilantro (aka Coriander), Basil, Nigella (aka Black Sesame, or sometimes Love-in-the-Mist), Chamomile, Oregano, Onions, St. John’s wort, Yarrow, Catnip, Valerian, Wormwood (Artemisia Absinthium), Parsley, and both Green Leaf Lettuce and Romaine Lettuce. (I’m also working on some Morning Glories for the backyard, but those are, um, NOT for eating.)
It’s such a wonderfully adaptable hobby, because most herbs can be grown (and very happily) indoors as well as out. I’ve been using A Modern Herbal as my primary source of information on most of this stuff (no, it’s not really modern—it’s from 1931), and I have been endlessly impressed, also, by the associated Mountain Rose Herbs. They sell bulk herbs as well as seeds, and their stuff is all organic, free-trade, etc.; but beyond that, I’ve found that they always ship quickly, and everything’s of good quality. I love their amber glass bottles for storing things, and have a little fleet of 4 oz ones that I’ve filled with both my herbs and theirs. (My most recent order from them included bulk Ashwaganda root, Suma root, Gentian root, and Hyssop; I’ve also gotten Shepherd’s Purse, which, though it tastes disgusting, works certain wonders; as well as Cocoa nibs; and Self-Heal, which I use in a sort of Witches’ Brew of various things that I have made in the past.)

(Sage and rosemary drying)
I’ve read a bunch of methods whereby people dry herbs in the oven, but I can’t figure out how this would be satisfactory. I’ve never had them come out tasting and smelling anything other than burnt, no matter how practically-room-temperature I cook them at, or how practically-still-fresh they look coming out. By contrast, I love hanging them: they invariably make whatever room they’re in smell totally delicious, and it’s pretty hard to fail with getting them to dry to a pleasant state. Anyone have any advice on the drying process?
Another amusing source of herbal information is at Crucible’s Herbal Guide. This is a website that is all about alchemy, and so they explain the herbs in terms of the elements and planets that they’re attached to, and some of their supposed spiritual implications as well.
I haven’t, sadly, found a good source of modern practical information about medicinal herbs, beyond Wikipedia (which is as wonderful as Wikipedia ever is—except that a lot of these articles are stubs, unless the plants are hallucinogenic, in which case there’s tons of information!)