Chong Nonsi BTS Station is located on Narathiwat Ratcha Nakarin Road above Chong Nonsi canal, it is close to the intersections of Sathon Road and Silom Road. This is part of Bangkoks business district so offices and banks are the main features of this area, also the Singapore embassy is located round the corner on Sathon Road.
Local hotels to Chong Nonsi include Om Yim Lodge, Narai Hotel, Sofitel and Tower Inn Hotel.
Another write up on the Om Yim Lodge.
On Narathiwat Soi 15 you will find many Thai restaurants and bars.
The Sathorn Thani building has a couple of fast food places if you need a farang food fix, as does Silom Plaza.