What do I use to get the finish on my work?
Most items are polished and buffed using the Beall system. Here is a great description of how it works.
I use Pentacryl to seal and preserve new "wet" wood that I collect, although some of it has aged and dried very well in my garage or under my deck, shielded from direct sun and weather extremes.
I've used Walnut oil and Tung oil, as described in the link above, to seal the wood and enhance the appearance of the natural grain, before buffing and polishing. Occasionally, when a turned and sanded piece shows beautiful grain or "personality," as I call it, I'll skip the oil bath and go directly from finish-sanding to Beall System polishing and waxing. Sometimes the difference isn't noticeable.
Although it's a bit more extreme than many other turners' process, when I sand a piece on the lathe, I progress through 50, 120, 240, 350, 440 and 600-grit sandpapers, ending with a Sorby-type rotating 2.5" disk with 800-grit facing. Then I put the Beall three-wheel system onto the lathe and progress through the Tripoli, White Diamond and Carnauba steps.
This process seems to work well for bowls, candle-stick holders and items with flat surfaces, too, although once in a while the buffing wheel can snatch a small piece out of my grip if I'm tired, bounce it off the lathe's cast iron parts and fling it across my shop. Sometimes I can repair the nicks or dents by remounting the piece back in the lathe and truing it up again; sometimes I just have to chuck the piece into the recycling bin. Such is life with wood.
Where do I get my wood?
I've bought many pieces of turning stock on eBay and from many online vendors.
A large amount of my "source material in the process of drying and aging" has come from stopping by the roadside and picking up "yard cleanup day" discards from neighbors.
A few really nice pieces started as chunks of firewood on the woodpiles at Hummingbird Pond near Asheville, NC, where we vacation for a week most summers. Yep, just plain stole the wood. Of course, that was after I'd gifted the owner with some nice candle holders, too.