Actually, I found that re-starting (in 2008, after all three of my part-time jobs fell out from under me) as an organic gardener on a zero budget was easier than it would've been as a conventional gardener:
1) materials for building raised beds -- free from Freecycle.org
2) materials to fill raised beds -- mostly free, some had to be paid for (peat, some of the vermiculite)
3) compost -- most of it mine; since I hadn't emptied it for a long time, the BioStack was pretty full! and refilling it comes from the kitchen and cereal boxes, shredded newspaper, scrounged leaves, etc.--also free
4) seeds -- used old seeds but gradually filled in with new ones. Fortunately, seeds for food plants are exempt from sales tax in California.
All told, DH and I got the first four boxes built, filled, and planted for less than $50.
Now, our only recurring expense is the plant starts, since we just don't get it together to start seeds on a regular basis. Too much else going on (esp. work at his mother's place, just keeping her house going...).
Sunset Zone 17, USDA Zone 9