I have just joined TNT this past month. This is my first event with them as well as my first big ride, America's Most Beautiful Ride in Tahoe. I was very nervous about the fund-raising part as well. The coaches and mentors have been extremely helpful with ideas to raise money, such as wine tasting events, yard sales, bake sales, letter writing campaigns etc... I have found the coaching, support and clinics really helpful (especially for someone who is just starting out). I have met some incredible "survivors" who ride with us (2 are our coaches) that really inspire and motivate.
I'd say go for it...