More books! Yesterday I found these:
The Complete Idiot's Guide to Music Theory, 2nd ed., by Michael Miller. ISBN 978-1-59257-437-7
Includes an Ear Training Course CD. This book explains all the foundational material you need to play: pitches, clefs, intervals, scales, modes, keys, rhythm, tempo, melody, chords, chord progressions, phrases and form, transcribing what you hear, accompanying, transposing, harmony and counterpoint, and plenty more. I am thoroughly enjoying this book, and have learned a lot. Like all those mode terms a few people on the forums here toss about. Like how to tell what the key is by taking a quick glance at the sharps/flats in the sheet music. And the CD showed me my ear for pitch is a little better than I thought. The author highly recommends you go through this book before reading...
The Complete Idiot's Guide to Music Composition, by Michael Miller, ISBN 978-1-59257-403-2
I started reading this one first, but before getting to far into it the author told me to hold the phone and get the basics down first, by reading Music Theory (above). What I did read I enjoyed. Some of the topics covered include composing with melody first and chords first, developing simple melodies in to longer compositions, creating interesting chord progressions, advice for orchestrating and arranging, employing traditional and contemporary techniques, selecting the right instruments and voicings to express your musical ideas, and more.
The author has other books on related topics (soloing and improvisation, arranging and orchestration, using Cubase, singing, drums).