Macbook Pro running out of hard drive space...

Look to getting a Windows XP PC (Do NOT get Vista, it's HORRIBLE), instead of just a "Training PC" you call a Mac. They're cheaper, and way more effective. Also, your "can't get things off of a back up if I delete them from the main computer" makes absolutely no sense. That would defeat the purpose of a BACK UP. :) If you put data on one hard disk, and delete it from another, it does not "poof" from the one it was put on, as if by magic. Data will stay on your backup drive untill you decide to do with it what you will, so there should be no wrries there. If you ABSOLUTELY must have a CrApple computer, I would recommend a ;larger hard drive, it would be much easier than an external one, but if it crashes or something happens to it, you have all of your data on it. Keep the external one as solely a back up, for important things. Hope this helps, and hope you can decide eventually to make the switch to better, more affordable hardware. :)