It's hard to build up enough compost with just kitchen scraps to feed a good sized garden. I would be on the lookout for cow, horse, sheep, rabbit, etc. manures, and other good soil ingredients in as large a quantity as you can afford. Be on the lookout on CraigsList for people wanting to get rid of such materials at a low cost.
At the same time, watch out for bagged soils that are "too good to be true". The 99 cent and $1.99 bags of "topsoil" or "compost" at Wal-Mart aren't all they're cracked up to be and often contain mostly sand and the scrapings from vacant lots. A good bag of composted manure should set you back $4-7 but a little of this black gold goes a long way. If you have to go with bagged compost, then a 3 x 12 garden bed would get a nice kickstart from 3 bags spread out to about 1 inch thickness and gently folded into the top layer.
I am a believer in peat moss, even though there is some debate over whether it is truly a renewable resource. It's cheap, and once wetted (you may need to add 1 tsp of Dawn or other dish soap per gallon of water as a wetting agent), really helps to loosen up soil and improve drainage.
I would extensively read the Gardening in the Green forum as well as this forum (Soilbuilding) and settle down on a list of ingredients you can get your hands on. Adding lots of organic matter is not the answer to every problem, but it's a good start.
A thick layer of mulch will help with preventing fungus spreading. In my last couple of years of gardening before I moved, I was applying fungicide really only at the beginning of the season as a preventative and had stopped over a month before harvest. Leaving enough space between plants and having a good layer of mulch (and watering in the morning with soaker hoses) really helps. The organic alternatives to fungicides have come a long way in the last 5 years.
I'm sure others who are in your region will have more advice about problems specific to your area, as I've only gardened in Houston which might be a tad different.
