Hi T M,
You've been given some good advice here and I too recommend the following route:
1. Get Licence
2. Join PFA to get a feel for what PFA flying is all about.
3. Join a group
4. If you still wish, buy your own aircraft.
Joining a group will give you both the ability to fly for a fraction of the hiring cost plus you will learn much of the ins and outs of operating an aircraft.
Not all groups will take new PPLs, but some will. Our group sometimes even has students in it. I think the insurers wanted a small addition to the premium when one low-time member joined but he paid that directly to the insurance company and it wasn't a lot of money. Many of our members have had less than 100 hours total time when they joined the group.
Our group of six share a Jodel D112 which is a two-seat wood and fabric aircraft with a cruise speed of 80 kts. It handles much better that a Tiger Moth, plus you don't get rained-on. We each pay £37 per month which covers all the fixed costs, hangarage, insurance permit etc, and then pay £6 per hour from take-off to landing (yes six pounds!) to fly the aircraft. We each buy our own Avgas and leave the tank full for the next member. So the total cost is about £23 per hour airbourne. Take a friend and cost share and thats under £12 per hour.
I'll probably fly this aircraft into Turweston for the fly-in on Sunday 16th so if you're there you can ask me more about it.