:s/\<search_term\>/\\index{&}/gc
This, with some more fudging with the replace string seems to serve my purpose for now. Thank You. However, I was wondering if there was already some sophisticated script or function written for this purpose explicitly that can handle all the various situations that may arise when indexing with Latex.
I came to know that Emacs has something like that. So, my mind just blanked out on using :s// Thanks Senthil.
