In reply to cuilcagh:
Where are you based? This time of year your local indoor wall is probably your best bet. You shouldn't need to buy any kit initially though you'll want shoes pretty soon if you get into it. Also, check out your local climbing/mountaineering club(s) especially if you need a partner to get the most out of your (mostly roped rather than bouldering) local wall.
Affiliated clubs (most of them) are listed somewhere on the BMC website, from memory it's not obvious but a search will turn it up easy enough. If you're under 18 you may have some problems with joining a club, they all seem to have different policies.
jk
