What's the relationship between VC funds, VC partners, and VC firms? Are funds typically associated with a specific GP, or are they associated with the firm as a whole? Does the firm offer only a single fund at a time, or does a brand-name VC (say, Sequoia, or Accel, or KP) have multiple offerings with different portfolio strategies?

Also, is there a good way to find out who is about to start raising money for new funds, and where in the lifetime of their fund a particular partner might be? (As in, have they just raised money and are looking for the first couple investments, or is the investment period about to close and the fund's capital has all been invested?)