The place I want it fitted is in a corner of a room where two walls meet at 90 degrees

You will want a full motion, or articulating, mount. Probably a 20" extension. You will want to measure the spacing of the holes on the back of the TV in milimeters. Chances are it uses a VESA standard.

As fara s a place near "old madras road." I'm not even sure what country you are in. Haha. If you're near a Best Buy, I know they sell the mounts. Just about any electronics store will sell wall mounts. But Best Buy actually offers services too. So if you're not looking to do it yourself, it's an option.

Otherwise local shops will sometimes have someone who does mountings also.

Look through here:
http://www.petra.com/tv-video/mounts-stands-furniture?cat=97
You can also mount on a pole from the ceiling, a motorized lift, and even a motorized mount that allows remote tilt and pan.