In reply to mjason:
Ask everyone you know if anyone they know likes to go hill walking/hiking etc. It shouldn't be too hard to find someone, even a friend of a friend will do.
Then tell that person you're interested in getting up mountains and would they mind you coming along one day. Offer to buy a few beers and split petrol.
It's worth checking that it's not their first time up a mountain too though!
I've had lots of friends/colleagues come with us on the odd weekend trip, many who haven't been near a mountain in their lives. It's a pretty amazing feeling (for both them and me!) when they reach the top of their first big hill.
Then just take it from there.
Don't go spending loads of cash on kit until you work out what you want to do (walking/climbing etc), where you want to do it (surrey hills or the Cuillin) and when you want to do it (summer or winter).
If you can borrow a pair of boots that fit well, then great. Otherwise some boots and a waterproof jacket are likely to be your first purchases. There's no point in buying a map and compass until you know what to do with it (it's not difficult, but you'd benefit from someone experienced showing you what to do). The only thing a map is good for if you don't have map reading skills, is to hold over your head to shelter from the rain whilst you wait for MRT at dusk after getting lost