I have had to import alot of my burl wood from Tasmania, but that is quite expensive as you can imagine.
My main source of the exotic's are from Greed Bay. Plus in the past I have befriended many exotic burl wood importers, and from time to time have received much lower prices, as a artist to artist relationship.
I truly believe that kiln drying is good for production wood (aka) framing woods and like, but for the most part, turners like to air dry their stock.
You can use a micro wave technique if you are pressed for time, but you run the risk of having small fishers, cracking when you do this.
My ideal moisture content is between 8- 12 %, and there are probes for finding the moisture content of wood.
Burl wood has such a high density, of tight grain that almost always they have a heavy, dense feel to them.
Many people still wonder how and why the stradivarius violin, has such a beautiful sound that eludes violin builders to this day. The secret is in the wood in the time that stradivarius was alive, In his day he experimented with all kinds of host wood, and then he chose a very small specific site of old growth trees. These old growth tress he chose had a very singular advantage to them, in the fact that the growth rings were so close and tight, from years of drought, that they had a unique tight growth pattern associated with them.
if you think about it, it makes sense. Being that you would do your own metal work on the cars you had, I bet you could tell by banging on the metal, you could find the bondo areas right away, thus leading to your success of using lead( which is much densor) as opposed to body filler. And yet using the technique of finding a stud in the wall covered by wall board, you can hear the density of the stud by the sound.
here is a link to some on greed bay