How to Use AppleScript to Find Computer on the Network and Launch VNC

Please note that I have asked this same question over at Apple forums: https://discussions.apple.com/message/29837859#29837859

I have a shell script I use in an AppleScript app that will launch Screen Sharing of a specific computer on the network. This is essentially the basis of it:

open vnc://user:pass@server:port

I saved the above as an AppleScript Application and it does it’s magic. However, if the IP address of the other computer on the network changes the script will not work. I’m an AppleScript hack and not really really good at all with the terminal so I need your help for this:

How do I get the other computer’s IP address and add it to the open vnc command?

Model: MacBook Pro with Retina display, OS X Yosemite (10.10.1), 16 GB RAM
Operating System: Mac OS X (10.10)