Poor man's buisiness education

[STLantny]

So, Im 23, know way too much about computers (BS information security systems), and while I do like the field, after getting into the business of tech sales/installations/maintenance, and even some restaurant bookkeeping. Ive decided I may want to steer away from the purely "tech stuff", and deal more in sales/finances, you know the whole "business world" deal. Can someone give me a reccomendation for some books dealing with sales, finance, the business world etc, so I can give myself a crash course in the next few months?