I think the 2 main places are Bodyheat and Esquires, although there are lots of private girls in the paper as well. Most brothels probably would be prepared to offer the service, but likely at full service prices, standard RnT is normally a bit cheaper. Bodyheat is exclusively RnT, but recommending where to go is a bit of a toughie as it's the individual girl who makes the difference. See if you can find any reviews so you've got a short list of names you'll recognise as possible goers. Private girls can be fantastic, and they can be terrible, other than reveiws it's hard to tell until you're already there, so if you go that route be prepared to have to try a couple before getting someone you like.
My main tip would be to be as freshly showered as possible before you go, and if you're looking for digital stimulation as well, try to time it away from when you would generally have a bowel movement. Don't be suprised if they want you to have another shower beforehand anyway - sometimes it's just their policy - but if you've been thorough at home it'll be a quicker shower anyway. Asking for G-spot massage with the hand job shouldn't be a big problem for the girls, it's not at all uncommon. It's the kind of thing you might want to check on before you pay though in case you've happened to hit on a squeamish girl - you don't want to be disappointed after passing the point of no return.
Personally I never charged extra for it when I worked, but again it's the sort of thing you need to check before committing yourself. I hope you get a good one!
