Amazon registers lobbyist in Georgia, sparking rumors about Atlanta’s HQ2 chance (geekwire.com)

A couple of questions:

  - Do all 50 states require lobbyists to be registered?     
  - How is this information (on registered lobbyists) made public?    
  - How would one go about compiling a comprehensive list of all of Amazon's lobbyists in all 50 states, and the date on which they were registered?

Answers to those questions might help figure out whether this is just a normal hire for Amazon, or a possible clue as to the location of HQ2 (which I'm as curious about as anybody, I suppose).