I agree 100% with tangentgirl, TNT will prepare you. I did my first century with them. Before I signed up, the most I had ever ridden may have been 20 miles. It was a time commitment with all the training, but on the day of the ride it was a piece of cake, they had totally prepared us. Our group was a mixed bag, I was afraid the team would be super athletic people, it wasn't.

As for the fundraising, don't be afraid to ask EVERYONE, you'll be surprised how generous people are. Send regular letters (with reply envelopes) and emails to people. Our TNT office had meetings to help us with fundraising ideas. Two of us on the team also had a fundraising event at a local restaurant -- we brought in over $1000. Since you've got the holidays coming up, maybe you could suggest people donate as in lieu of a gift?

I ended up raising $5000, my commitment was $1500. (Although my dad died of leukemia, and my aunt has lymphoma, so I it was easier for me)

I'd be happy to share my fundraising letter with you if you'd like additional samples.

Good luck!

Go Team!