My god that sounds fun- referring to Jacqi C's Tour stage ride. In a year or two- I've been hurt. It's a pilgrimage.
How experienced are you? You need a training base of long slow distance for conditioning- the speed comes. When you're fit enough you need training rides of a minimum of two and a half hours regularly- thats the point at which the body makes the big training adaptation.
I'd look around for a good club to train with. Knowledgable people, structured training rides, moral support. Books are excellent but they ren't much fun on the road in the cold. Racing clubs often have non competitive members and that might be a good resource since they'll have a coach or at least know who you should talk to. You can get a century training schedule from almost any cycling mag, but the climbs are going to be the sheep killers. If you want to be the goat it will take technique, and live people to teach and tweak and push you when you need it. The Dance of Lance, that beuatiful high cadence spin, a good club will go out and ride drills on this kind of stuff and you'll have it to get up those climbs. Find a club you like- these are the people you'll get cold and wet riding into the wind with all winter and then drink with after so you should be on the same wavelength.
Keep us posted! How exciting!

missliz