If going to a brothel is on your list of things to do by all means but there so many wonderful ladies in LV
Never been but if you must go the closest is about a 45min. drive to Pahrump via Blue Diamond /Hwy 160 -I think (correct me if I'm wrong)
 I'd advise you to save yourself the trip and $ and spend some time with some of the amazing ladies in Vegas

Dennis believe that happy girls bring happy customers so the ladies working at his cathouses are treated way better than the ones in other legal brothels (known by many of us as pussy prisons). The closest ones to Las Vegas are Love Ranch Vegas and Alien Cathouse (yes, its is Alien themed). If you decide to visit Alien between mid to end of June, please say "Hi" to my "evil sister"  Goddess Vienna and her beautiful friends. It will be between 1 hour to 1 1/2 hour drive from Vegas.

The ones closer to Reno are just 1 hour 15 min flight away from Vegas and are larger (more options of girls) than the ones close to Vegas. If you have an appointment with one of the ladies, they can send a car to pick you up at airport (cheaper than a cab). Up north you can visit the famous Bunny Ranch and only 4 minutes away you have Love Ranch North (sister house to Bunny Ranch), Sagebrush and Kit Kat Brothel.

It's a bit different  than scheduling a date from an independent provider (among other things, sex preferences/practices  can be openly discussed during negotiation and you end up in a house full of girls where everybody knows what you are there for, but no one cares-in a good way), I think that if you've never done it, a visit is surely an interesting experience. As it was mentioned on a previous comment, it's the law that everything has to be covered (play safe) at all time.

Have fun & stay safe!