I'd recommend "Practical Interfacing in the Laboratory" By Steven E. Derenzo
This book was used in one of my classes in school and does a good job of presenting a bunch of useful and practical techniques. Its geared towards Data Aquisition and control with a PC but most of the stuff is the same or really close if you use a microcontroller. It covers all sorts of useful topics like switch debouncing, Analog filters, aliasing, handshaking, digital filters, Signal amplification, etc. in a very understandable non-mathy way. It also has lab excercizes (Interfacing an A to D and DtoA, TE Cooler control, EKG and some other cool ones) that list all the parts you need to do them. You will need some basic knowledge of electronics (resistors capacitors logic gates) and being good with algebra will help you follow some of the analysis of analog filters but other than that it is a very accessable book.