I doubt if there's a book that lists the differences between each state. Perhaps in a law school library or bookstore, but that might be a bit expensive. Most sources out there would point you to the Secretary of State or Comptroller for each state in which you're interested. In TX, state sales tax is charged on the purchase of an airplane UNLESS it's an "occasional sale." That means that John Doe sold you his plane, and he's not normally in the aviation sales business. If you buy a kit and build your own, you owe TX sales tax on the kit, regardless of where you bought it, unless the state in which you bought it also charged you tax. No double taxation that is. If you buy stuff out of state, the TX tax is called "use tax" but it's the same thing, at the same rate. I bought a Cessna and didn't have to pay. I bought a kit, and paid.