I think I decided that I may be getting a BTS in the near future, but I need to do my research first.

What breeders are out there that have these animals available?

What is the difference between the different regional blue tongues? I've seen northern, eastern, and western BTS. Which one is the most common, best tempered, easiest to care for; etc.?

What basic care should I worry about. I know UV lighting and temperatures for the most part, but feeding is something I'm a little more confused about. A lot of caresheets say 60% plant, 40% meat with meat items including canned meats or dog food and super worms.
What would be a good substrate for these guys? Can I use tiling or are they big burrowers and need more than that?

Thanks,
-JW