Said it before in other threads, call the phone numbers you see on old fashioned prossie cards stuck to the inside of phoneboxes in prossie hotspots such as Paddington, Edgeware Road, Covent Garden, etc, etc. Ask how many girls they have working, and the price. Rates for Edgeware Road - £80 for 30 minutes; £60 for 20 minutes. This is for a basic service - expect to be offered various "extras" when you get there, for extra coin.