Hi Vaibhav,
Where all have you already looked for initial info, and over and above that what is missing that are you still looking for?
Possible sources for metadata:
For geospatial data, you can get into the data extraction side of Openstreetmap - the open-data alternative to google maps which lets people extract specific data out of it.
If you navigate to NCR region and open Wizard and put in "railway=station", you get a lot of hits. But these may also include the regular railway stations, so you can select a positive result, see more tags there and refine your search further.
if we change the query in the Wizard box to : railway=station and network="Delhi Metro"
..then it gets better.
Similarly to get the metro tracks you'll need to search by other tags.
Once you've got a good query, can export the data to a shapefile for working on.