Below are tips and stories from my experience thus far:

How Much is enough??

I used the NOLS ration system to estimate how much of everything I would need. Their formula predicts that a person eating 2lbs of food per day (which is almost exactly how much I, a 150lb woman, have always eaten on previous trips) will eat the following break down:

I multiplied these amounts times the total, for example:

2lbs X .42 = 16% trail food
16% X 230lbs (the total amount of food for my trip) = 36.8 lbs trail food

One problem with all this has been that I am using dehydrated foods, and NOLS uses mostly "fresh" food. I've adjusted accordingly- through guessing equivalents, and came out with about 1.3 lbs of food per day- I'll find out on the trail how well this method works!

Dehydrating

The biggest help here was Mary Bells' Total Book of Dehydration. Below are some of my experiments and some standards. I used the American Harvester, with six trays and made my own solid trays for drying liquids by taping plastic over the trays.

Tomato Leather:
Cover tray with solid plastic (I cut up plastic bags and taped over the tray) Lightly grease Spread about one large jar of tomato sauce evenly over the tray Dry about twelve hours at 135 degrees. Leather should be brittle, with no moisture.

Soups:

Soak 1 lb dried beans (chickpea, turtle, pinto, black eyed...)
Pick a broth (stewed tomatoes, curry, vegetable, kombu...)
Cut up 1 lb vegetables (carrots, broccoli, onions, potatoes, squash)

Throw everything in a pressure cooker, fill 3/4 with water, and cook following pressure cooker directions (usually 8-15 min.)

Transfer in batches to blender, and pour from blender on to greased solid plastic trays. Dehydrate several hours and then flip soup (now in semi-dry chunks) to dry other side. Soup should be powdery and crumble when totally dry.

Fish (or tofu):
Skin and bone 1lb fish (I used haddock) cut into thin strips (1/4 inch)
Soak for 8-12hrs in 16 oz soysauce, 1 cup sugar, and 1/4 cup blend of fresh ginger and garlic.
Dry on solid trays for about 12 hrs at 145 degrees. Flip half way through.
Finish by putting strips in oven for 20 min at 200 degrees.

Other stuff I made just by cooking or thawing, and then drying. All it needs on the trail is a few hours of soaking in my tupperware as I hike down the trail.

Tempeh
Seitan (wheat gluten)
Rice - all kinds
Vegetables (all from frozen) - corn, peas, carrots, tomatoes, raspberries.

I stored all my foods in the freezer until I was ready to pack them up. The fish will remain refrigerated until my sister or mother send it along with the rest of the food for that resupply.