This fellow Bill Walsh has been doing what I do, for nearly as long as I've been doing it. He wields a red marker. He uses it unmercifully. He's my sorta people.
The Slot explains to the curious what a copy editor is. For a good time, I read Walsh's Sharp Points columns and watch his blog about editing errors he finds in newspapers that ought to know better. Too often, I discover I've been making thoughtless editing mistakes of my own. It keeps me on my toes alert.
Are there online resources that help you stay up-to-date on your own career? Do tell!