Configure to Select DNS based on Domain
What you're describing is a split-horizion DNS setup.

There's a pretty good walkthrough on how to do exactly what you want to do, but it will require root on your laptop and some command line patience to setup.  In a nutshell, you'll be configuring your own DNS server on the laptop to forward your DNS requests to the right server.

If you're on Mavericks (not sure yet about Yosemite), it looks like bind isn't installed anymore.  You'll want to get it with homebrew or similar.  Check out this stack overflow Q/A. It should also have a default named.conf that you can just edit, but YMMV.