Totally agree with KimKim. This forum provides tons of information about training, nutrition, behavior and lots of opinions from loving grey owners. Also you can find online many trusted sources. Just read and once you get your grey you will start developing your own experience. I dont see that you have to pay money to listen to someone's advice when you dont know how reliable it is or when you can get even better advice for free.
If I were you and I was planning on getting a grey, I would start looking for a decent breeder, pay him/her a visit, observe the grey, ask as many questions as you want. Once you get your grey, invest in a good avian vet visit to make sure he gets a health check and after that you need to invest your time and effort with your grey to make sure he/she lives a happy and healthy life eating the right food.
Good Luck