Network Drive File Search – remote access

I have Network Drive which can be accessed remotely via a web page and then browsed by a file directory.

Due to the shear volume of files I have on it and my need to find specific files (ie I am searching a sound effect library for gun shots) I need to have a web based search engine to browse the drive. I have done some research and have come up short with an inexpensive (which is to say free) software or web based indexing search engine. Any thoughts?