Following up on Endi's Sculpt tool tutorial earlier this week, Frederik Storm has published a highly detailed character modelling tutorial. It's an intermediate-level tutorial, so you may first want to learn some basic concepts by digging around this site (see the related post and search function) or the Blender Documentation Wiki.
A few words about this tutorial/walkthrough, I made this to show how I get my ideas form my head, to the paper and then to 3D. When you read this tutorial/walkthrough I don't want you to say, â€œSo that's the right, the only way of doing itâ€, because it isn't. This is made to show how I do it, and hopefully give you some knowledge, and ideas on how you might do it next time.