Here's something I wasn't aware of, but I'd bet many of you are quite familiar with: The International Catalogue of Superheroes. It has a nice overview of Jack Staff, by the way.
Which brings me to the good news/bad news department. My comics shop got short-shipped yesterday on Gotham Central, but did manage to score me a copy of Jack Staff 12, which more than made up for the disappointment. So hopefully I'll get my copy of GC next week.