I am by no means anything close to being an expert on the subject, and it is very likely that you know about this, but what the hell, right? Everytime I go to the bookstore, I usually browse the business/economics/finance section for something to read. A good chunk of the books I find there are related to being a manager and that sort of thing. I haven't read a single one so I wouldn't know if they are helpful or not, but it might be worth a try to at least check them out.
