Who's your ISP AMDave?
My connection at my grandparents in Warwick is 2mb ADSL which is £29.99 pcm unlimited. At Emma's parents house, they have NTL which is 6mb and also unlimited (although I hear there's an informal 30gb pcm limit)
WoW doesn't use a GREAT deal of bandwidth, in fact you can (just about) play on dial-up.