Patpong is located near the commercial hub district of Silom. Although only consistent of one main street Patpong is filled to the rafters with go-go bars, English pubs and small dance clubs. And in between these seedy establishments filled with scantily clad women gyrating their hips to techno beats on stages is the famous outdoor Patpong Night Market located right on the street that is closed off to traffic starting at 5pm. There is an ongoing joke that in Patpong's Night Market you can find fakes and knock offs of Rolex, Coach leather goods, brand name clothes and woman. Yes even some of the woman there are fake and in Bangkok they are considered the minor third gender called simply Lady-boys.
To experience the best of Patpongs nightlife offers it is best to stay in a hotel near or around the area of Soi Patpong. Now Patpong as I mentioned above is just a small street. It is sandwiched between Silom and Surawong which are major thoroughfares on the map so you can not miss it. Patpong is also close to Soi Thaniya or Japan Town (Another nightlife scene you should not miss.) That are lined with female hostesses appealing Japanese clientele. These areas are also where the best hotels are located in. Hotels such as the Montien, Silom Serene, Baan Heritage and the Tawana Ramada. Staying near these hotels is a good idea because they are very close to two of Bangkok's fastest mode of mass transportation, the BTS Skytrain and the MRT underground train system.
Traveling onthe BTS and MRT is a great way to avoid Bangkok's ridiculously congested traffic nightmare and cheap. It will take you to the major commercial shopping centers such as Siam Paragon and the Emporium as well as other nightlife hot-spots such as Nana Entertainment Complex and Soi Cowboy. Best of all, the MRT and BTS are ice cold air conditioned and believe me you'll appreciate it.
As far as when to go I would suggest between the months of October to early April which are the cooler months that the high season. The rates for hotels are higher but still still affordable because of the advantages of the Western currency exchange rate. You will also get a better deal in terms of room quality for the rate that you pay at a Western hotel. I notice the rates that I pay at a motel or hotel in the United States, I can book a 4 or 5 star hotel in Bangkok with free international buffet breakfast that includes an omelet station. I'm not kidding. The difference in hotel room quality and service is between night and day. But of course the same rule still applies here as well as anywhere else. The more you pay the better the qualities in room and service you get. So do not expect to pay $ 20 US dollars a night for a hotel with an Olympic sized pool and a decent gym. Although you still might get a pretty decent free breakfast.
No matter which hotel you choose I suggest you check out the reviews first. Many hotel reservation companies have customers who give updated information and reviews about the hotels they've recently stayed in. Do not rely on the hotel reviews that you see on guidebooks because the information will be outdated at the time of print. Bangkok hotels go through frequent renovations so an updated review can give you an advanced warning. My last final advice is relax and enjoy your trip to Thailand.