"You and a partner go into business together and split the equity 50/50. You do all the work and your partner slacks off. He owns half your business- now what?
Slicing Pie outlines a process for calculating exactly the right number of shares each founder or employee in an early stage company deserves."
This is the book I wish I had read before my first startup because it takes the emotion out of it and really helps you take the founding process seriously right from the start.