There are zillions of videos on youtube on how to convert an electric kiln to gas. You may be able to pick up an old beat up electric kiln from craigslist, convert it to gas, and see if you are going to like it before investing (and we are talking $$ here) in building a kiln. As far as clays go you do need to decide what cone you plan to fire to and many clays will work for reduction or oxidation. If you are looking at gas you will be firing in reduction. Read down through the clay descriptions and find one that is for wheel work and fires to the cone you are interested. I would ask your clay supplier for a recommendation. They will know what their clients like best.
Again, you can watch videos on youtube and get lots of free instruction but remember, often free advice is worth exactly what you pay for it I too first learned to throw in high school and then took weekly private lessons from a potter whose work I admired. Her technical skills are impeccable. That may work for you if you cannot find a community college or art center to take lessons at.
You may also want to consider picking up some raku clay and do some pit firings just for the learning.
Working with clay is a real roller coaster, complete with great highs and low lows with a pretty steep learning curve. And, considering potters work with "dirt" it isn't cheap to gear up for. Enjoy the adventure.
1. people order pieces and don't ask you to change anything
2. you cull ruthlessly *after* you have put handles on mugs and finished all steps to berry bowls but before bisque firing. (i recently tossed two berry bowls because the holes didn't come out exactly as i wanted.
3. you wash the glaze off a piece and redo it because you have learned through trial and error that proper glazing does count and crappy "get by" glazing ruins a great pot.
4. when you can recreate the same shape over and over, even if you don't want to.
5. you set aside a large trash can for fired pieces that don't cut the mustard and smash the pieces in it so that you (and others) aren't tempted to save them
6. and most importantly to me, you continue to try new things and take risks that can end up in the reclaim pile/trash heap.
First of all, I don't recommend this practice with anything you care about! But that said last weekend I was doing some stamping on mugs and couldn't find my favorite stamp so just for giggles I made another and stuck it on top of the hot wood stove, Much to my surprise, it was dry in minutes still in one piece and the squiggle I had added to a post was still attached. I throughly expected the thing to crack or fall apart, or for the squiggle to pop off, but when it held up to use I got a little more bold and tossed it *in* the wood stove to see if I could blow it up. Still nothing. I made a few more and will bisque fire them the next time I do a load.
I wouldn't recommend this with a larger piece or anything you cared about, but I'm trying to say experiment. If you are a scientist then you know what I mean when I suggest that you try new things, push the tested boundaries and take notes. One thing you can count on in ceramics is that nothing is always predictable or the same, and just when you think you have it all figured out, ###### happens.
The wonderful thing about clay is that it is reusable over and over, if you don't fire it. I've learned valuable lessons by making and reclaiming pieces over and over. I think I used and reused my first 50 pounds of clay for 6th months before being happy with enough pieces to bother firing up my kiln.
My pieces always feel cold to me no matter how long they have been sitting on the shelf, so I go by how they look and feel in my hands.
The only piece I have ever had blow up on me did so because I was doing another experiment. I decided to try spraying glazes on greenware. I usually bisque everything. The piece was definitely dry when I sprayed it but I put it right in the kiln and programmed a fast glaze fire… dumb dumb dumb but hey, that's how we learn right?! I guess for me, the joy is in the journey.