bigbalu,
I will assume since you are posting this in a Linux forum...that you want a Linux solution. Here is a good article with a few choices. I have not used any of these myself, but that is about to change.
http://www.linuxscrew.com/2012/04/04...ment-software/
There are also some Windows-based solutions for IPAM, such as infoblox and solarwinds, that offer a free solution, but functionality is limited.
The hard part about your request is the specifics that you want. It is sometimes hard to find opensource software that actually custom-fits all of your needs. If you knowsomeone that is pretty good at basic programming/bash scripting, you could modify a simple pingsweep script with a a few additional commands and get the desired output (CSV file). You could then open the CSV file in LibreOffice or OpenOffice CALC and print to file (PDF). It may take a few steps to get the desired output, but it will still be far fewer than the manual process that you are currently using.
Good Luck!