I was a 50 year old rookie this year. You have picked a great place to start as there are many smart people on this forum and you will probably get a lot of great advice. You can look through all the old threads and read what interests you. I would also spend alot of time at
http://usfirst.org/roboticsprograms/...lt.aspx?id=966. There are many videos at
http://www.thebluealliance.net/tbatv/. My favorite video is
http://www.youtube.com/watch?v=Wysi3s7h0qA, the final match in Boston this year because it captures some of the excitement, but I may be a bit biased.
Just be prepared for a lot of work and a very rewarding and fun experience.