Is there any sort of indexing software/plugin that will allow me to tag clips with descriptive keywords so that I can easily find these clips at a later date?

You can tag clips with keywords, etc and search/browse through them by the tags you set in Adobe Bridge. Check out the "Managing Media in Adobe Premiere Pro" video workshop Adobe offers at http://www.adobe.com/designcenter/video_workshop/ (also on the video workshop disc that comes with some Adobe product (I recieved it with CS3 Production). If you select Premiere Pro CS3 as the product, the video is the 7th one.

Thanks a lot Brandon. I'll check this out. :)