Have you got a sequence set up with your two cameras synchronised on different tracks?
If so, then the quick and easy way is to use the crop effect on the top track and adjust is so that you see half of camera 1 and half of camera 2 in the program monitor.
Try the fast colour corrector first: put the effect on camera 2 (the green one) and use the colour balance dropper to set the correct white balance. Do the two cameras match better now?
If not, what you can try is the RGB curves effect instead. Adjust the curves by eye until camera 2 matches camera 1.
This is much easier then going the Speedgrade route for something so simple.
If you don't know how to use Fast Colour Corrector or RGB curves, then there are lots of tutorials out there on how to use them, as well as the help files.
The technique wouldn't necessarily be any different than it was before. Apply your preferred color correction effects to the original clips.
Thanks Mark, what I saw was in Speedgrade however what you suggested worked great! Thanks... I now have the clips a lot closer in color matching (using the crop and then fast color corrector - oh and then remembering to turn off the crop )