A properly structured workflow is essential for knowing where your images are, how you work on them and to protect Jpgs from degrading by saving them too often.
(If you didn't know frequently saving Jpgs makes them fall apart - check out the File Formats film).
There's a lot of digital workflow software available from Adobe Bridge to downloader programs that come packed with your cameras. I only use my computer's own file browser and a file re numbering program.
Why? I find it easier to manage my workflow files myself. Maybe I'm a control freak! Because my files are spread across many external hard drives I find that by naming the drives and making backup copies of them myself the structure is maintained better. When I've used software file management systems there have been bugs in the works which sometimes means the computer can't find what I'm looking for. So I have to spend time figuring out what's gone wrong - and I don't like that.
Once you have your digital workflow in place and a structure to work to you never need to do it again. You'll be able to find you images easily - and ensure you don't accidentally save over and lose any!
7 Steps to Perfect Pictures has taught me how to gradually build up adjustments and revisit them. It has also introduced me to a creative workflow and given me considerably better knowledge of LR's capabilities. Mike has a very natural, easy-going and relaxed way of explaining things which hold the viewers attention.