I don't know if there are tutorials, but I enjoyed Ben Cox's writeup [0] about making a driver for a vga / webcam he had bought. The osdev wiki links to this 2006 [1] sample driver project. Maybe you can find more, depending on what you want to interface with.
This writeup was immensely useful for me. Had all the information and pointers I needed to get started. My user space USB driver was significantly simpler, just control reports, but I don't know what I would have done if I hadn't found this article.