So, I'm planning my first actual touring ride from Portland to San Francisco at the end of the month. I've never done any touring before and I'm wondering what the best way to handle food and equipment is. I've got a tent and sleeping bag, and a nice touring frame that I could set up with panniers as well as a trailer, although that's pretty big and heavy. What I'm curious about is how much and what type of food/water I should have packed at the start and any other tips as far as equipment and operations go.
Assuming you're following a more-or-less straight line, water is about the least of your worries... Though you may want to invest in a filtration system so you can drink from the multitude of rivers, streams and creeks that you will cross.
For food, what do you like to eat? What can you afford? If you're planning on camping, buy a couple days worth of groceries as necessary. I prefer grocery store stuff to freeze dried 'camping' food. The grocery store stuff tends to taste better and cost less. If you have the money for freeze-dried, you may as well eat at restaurants every day.
For gear, use what you have. I recommend aiming for lightweight to ultralight packing, but feel free to compromise for your comfort as necessary. Ray Jardine has written a bunch on the subject for backpackers, particularly in 'PCT Thru-hikers handbook.' Most of the same theories will apply to bicycling. Otherwise reference the links above, plus adventurecycling.com.