A three year wait list? Uh, no, never heard of that. DFTW doesn't even book that far ahead. I would suggest you decide when you want to get married and call them to find out how far ahead they can pencil you in. I believe there is some sort of lottery system in place when many brides are competing for the same date (?), but a 3 yr wait list is just absurd and not true.
Not true. The absolute earliest Disney will even really talk to you now is 16 months for a wishes (20+ guests) wedding or 9 months for an escape (18 guests or fewer) wedding (I think it used to be 18 mos for wishes and 10 for escape but they've lowered it recently). You can only be pencilled in at that time. The consultant will take down your top three date/time location preferences at that point.
For a wishes wedding, if multiple couples want the same date/time and location they will do a lottery at the 12 month mark. If you're the only couple on your date, you'll be sent your contract at that point without a lottery taking place.
For an escape wedding, the lottery/contract happens at 8 months.
You need to have an idea of when you want to get married to begin the process. The consultant you talk to can give you an estimated proposal based on the info you provide but they won't confirm prices until you're 6 months out or less.