haven't paid any attention to books, tho I'm sure there are some out there. I learned it in a class and got experience doing in on the class project. It's almost too simple to need a book for it...Here are two videos I found about it. In the second one, she explains the difference between the front load and top load, or drop-in bobbin. she shows that you need a separate bobbin case for bobbin work, and that may not be necessary for the drop-in.
PM me with any questions you may have and I'll try to answer them....it really is easy to do.
http://www.youtube.com/watch?v=cH-AR...eature=related
http://www.youtube.com/watch?v=1MaOW...eature=related