Regular potting soil will work.
For starting seedlings, I would recommend mixing a one to one ration of potting soil to vermiculite (white puffy mineral).
For the plants themselves, regular potting soil. You could mix that with peat-moss, about 1/4 peat-moss.
I would look for ORGANIC fertilizers, a good 10 10 10 will work best. Follow the direction on the bag/can.
Why the Vermiculite? It lightens the soil and holds moisture, providing seedlings with a very loose soil to root in.
Peat moss needs to be soaked in water, it is extremely dry and compressed in the sack. It will swell and it will hold lots of water.
Further, it decomposes and feeds the soil. You can re use soil from year to year just as long as you do not plant the same crop in the same soil year after year. Rotate for three years.
Soil that you have used can be sterilized again by placing it on a sheet of black plastic and covering it with a sheet of clear plastic, setting it in the sun for a few days to bake.
I would advise getting books from the public library on small gardens, organic gardening, and alternative gardening methods to learn about soaps and homemade pest control.
you might get some ideas here
http://www.rain.org/~philfear/garden.htmlhttp://journeytoforever.org/farm_pest.htmlhttp://ohioline.osu.edu/hyg-fact/1000/1257.htmlThe last is a fairly good site on intensive Organic Gardening. Many of the ideas in it can be adapted to use for a potted garden.
Cheers
David