If you live in an area with a large Latino population, check out Mexican stores for spices. Especially popular with this community are cinnamon and cumin, which you can buy very inexpensively. They don't go in for things like basil and tarragon, but they do have good varieties of marjoram, oregano, bay, thyme, and a lot of things whose names you can't pronounce. Also they have more varieties of peppers than you can imagine, dried and fresh.

BTW, you don't need a dehydrator to dry herbs. Grow your herbs in pots (or the ground, if you have it). When they reach a point where they want to go to seed, cut the stems back. Gather these together in a kind of bouquet and tie with string at the cut end of the stems. Form a loop at the free end of the string. Use this to hang the herb bunches from whatever handy place you can find--in the garage, in the kitchen, on the balcony. All you need is to have the air circulate pretty freely around them. Soon enough, they'll dry up nice and crispy.

Crumble them up and put them in saved jars. Keep in a cool, dry place.

You can make fines herbes by mixing equal parts parsley, chervil, and tarragon.