At our giftsforengineers.com site, we use ZenCart for the front end, but 100% of our backend was written by me. In the course of working through some personnel changes here, it's forced me to take on additional responsibilities which have also caused me to take a closer look at my own code. The majority of my code was written some 6 years ago, with some additional modules added on as needed as the years went by. It's clear to me that our whole system could use some major reworking, if not a complete rewrite.
I know how I personally tackle a project like this but I am looking for helpful resources and some different perspectives before I jump in. I considered purchasing Martin Fowler's "Refactoring" book, and I already have "Code Complete" -- but I'm really looking for new-ish articles from other people. I think my database is fine, so I don't see this as an issue... what I'm really looking for are good articles on refactoring code. I've googled and found a few things, but I'd like to get an opinion from the peanut gallery. Feel free to comment here, or you can send me a tweet to @ElizabethN.