If you're really serious about tailwheel, vintage and display flying, you could do worse than Cambridge Flying Group. They're the group that operate two Tiger Moths at Cambridge. Tigers are great for teaching tailwheel finesse and are equally happy with a three point and wheeler landings. They also teach you about the finer etiquette of operating vintage aeroplanes.
The other route to consider is to buy a share in a relatively simple, inexpensive tailwheel type. A smaller-engined Cub is a perfect example. These are great for building experience and, in the right conditions, developing your confidence and competence in tailwheel taxying, take-off and landing one, two and three point, all of which have more opportunity to bite if executed badly. Pick the right conditions to practice and you'll find the aeroplane will teach you more than you might think.