which bar or club you choose will depend entirely on your looks, your bankroll and your game. There are plenty of upscale ones, but if you can't pay for bottle service, it's not worth even trying. Tao, 1Oak and others etc.
ECCIE is the site I swear by and if I am doing well at the poker table, I consider anything up to 500 fair game, top indys only or 100 proof. LVfever has some decent ads, although fewer these days. EROS can help only with visiting ladies with decent reps. Any agency other than 100 proof should be avoided, plus anything in a flyer, card or billboard, they are all ripoffs.
Casino girls used to be an option, but you have to be super careful now as others have said. if you want to try, sit alone in any bar in a strip hotel, they will find you. There's always strippers too, many offer takeout, but it's not cheap.
Civilians are a crapshoot.