There have been a lot of threads started here seeking basic info on RC jets. One of the best primers on jets is written by Mike Cherry, the founding editor of R/C Jet International (RCJI) magazine. The softbound book is simply entitled "Mike's Jet Book" and was originally published in 1997 (ISBN 0 9531150 0 3) and distributed by Traplet Publications <www.traplet.com> who also publish RCJI, a must-have subscription also.
In fact, I think Mike's book has recently been updated. My advice? GET THE BOOK! All the basics are covered plus an intro into the more complex stuff.

Mike (not Mike Cherry)