Ballet Dancing can be very easy to get into and very rewarding. Apart from being a very good exercise, Ballet is fun to do and creates flexibility and great posture. It is never to late to start learning and improving on your ballet skills. Getting started is as easy as buying the basic ballet items and finding some of the terrific local teachers and teaching studios available.
Online there are many great resources to help you start out. From beginners articles and tips, to more advanced techniques for intermediate and advanced dancers. I also highly recommend that you go to the useful online forum / message board to find ongoing discussions regarding beginner issues. These forums can help you progress rapidly and try new stuff.
Finally there are some reliable online stores for buying any ballet clothing and accessories. I also recommend some terrific ballet books, ballet dvds, and ballet music classics.
Good Luck and Have Fun,