You cannot go wrong with a Paul C Buff light, either Einstein or Alien Bees, and a few modifiers, they hold their value exceptionally well and if you hate it you can get 80-90% of your money back on eBay.
As for modifiers, it depends on what kind of image you like, post some links and it isn't difficult to reverse engineer the lighting of them to point you in the right direction for your needs. But be aware, the shooting environment plays as large a part in the lighting as the lighting does, anybody offering you advice without knowing what kind of images you like and what your normal "studio space" will be is disingenuous, their advice will not help you.
So much good advice really early on. I think I'll be starting with some off camera flash and some lightweight/travel umbrellas.
You're right about the shooting environment too. Lots of things I've got to consider.