You don't need a business account but you do need a personal account (or rather a personal account can be a business acct).

The targeting is relatively specific. Think of a (general) category and it'll be available. I use it for bars and restaurants at a local level, and the granularity is quite nice vs other media (target people who like bars or restaurants, are into music, are into drinks, are into cocktails, are into concerts currently in the city or who are traveling to this city)

It really helps a small budget go a long a way, assuming the stats they give are correct.