I'm working off of a hard drive and went through and selected, starred and edited all my photos in a catalog. Before I exported the jpgs, I accidentally unplugged my hard drive and now when I plug it back in, my catlog is gone and when I re-import the .CR2 files, none of the stars or edits are there. Is there a way to access a previous import with edits?
Reimporting images is not a solution. Lightroom stores all of your changes and your star ratings and everything else you do in Lightroom in the Lightroom catalog. The images remain completely unchanged from their original state on the hard drive. The catalog is that catalyst that makes everything functioned properly. Unplugging your external hard drive should not have caused you to lose your catalog. Are you using a single catalog, or are you creating multiple catalogs? The only way you will get those adjustments back is to find the catalog that was used when you made all of those adjustments and star ratings. It should be somewhere on your computer. Take a look at File->Open Recent and see if there are other catalogs listed. It's possible that you have opened a different or a new catalog, and that's why you can't see the images you were working on.