The guy you talked to on the phone was probably Gary, the company recruiter and comedian.
The ground school is 95% straight off of
http://www.austincollins.com/archive.htm Everything you will be tested on is in here. I suggest printing off all of this material, and reading and learning as much of it as you can before you get there. Your ground school instructor will be Austin Collins. He is a very good teacher, but there is a lot of stuff to cover in one week. Pay particular attention to the Cessna 210 Flight Training Handbook. While you are in ground school, make sure you spend some time sitting in an airplane practicing your flows and checklists.
Study hard and you will be fine!