I just did a crosspost on both of my other blogs about an online book that looks to be quite interesting, called All About Tobacco. Written by a tobacco industry insider and published in 1970. It includes information about how tobacco is handled, processed and flavored; how pipes, cigarettes and cigars are made, and other stuff. Some of the manufacturing information might be dated by now; I'm sure technology has changed since then.
Anyway, check it out if you think it might be of interest, here or here.