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Books On Music Worth Keeping Around
By an Amazon.com customer
The Harvard Dictionary of Music (Harvard University Press Reference Library)The Harvard Dictionary of Music (Harvard University Press Reference Library)
Buy new: $31.50 / Used from: $24.07
The Harvard Biographical Dictionary of Music (Harvard University Press Reference Library)The Harvard Biographical Dictionary of Music (Harvard University Press Reference Library)
Buy new: $29.75 / Used from: $8.90
The Development of Western Music:  A History.Third EditionThe Development of Western Music: A History.Third Edition by K Stolba
Buy used from: $14.00
Tonal HarmonyTonal Harmony by Stefan Kostka
Buy new: $83.60 / Used from: $66.00
From my experience, this is a great book for laying the foundations of music theory.
Workbook for Tonal Harmony: With an Introduction to Twentieth-Century Music, Sixth EditionWorkbook for Tonal Harmony: With an Introduction to Twentieth-Century Music, Sixth Edition by Stefan Kostka
Buy new: $48.66 / Used from: $48.11
The accompanying workbook.
Musical Structure and DesignMusical Structure and Design by Cedric T. Davie
Buy new: $8.54 / Used from: $1.71
Music for Ear Training (Workbook & CD-ROM)Music for Ear Training (Workbook & CD-ROM) by Michael Horvit
Buy new: $98.95 / Used from: $15.56
Like Tonal Harmony, this book is fairly good for a foundation in ear training.
Music for Sight SingingMusic for Sight Singing
Buy used from: $97.00
Useful in conjunction with Music for Ear Training.
Analysis of Tonal Music: A Schenkerian ApproachAnalysis of Tonal Music: A Schenkerian Approach by Allen Cadwallader
Buy new: $55.87 / Used from: $47.44
Student Workbook to accompany Analysis of Tonal Music: A Schenkerian Approach, Second EditionStudent Workbook to accompany Analysis of Tonal Music: A Schenkerian Approach, Second Edition by Allen Cadwallader
Buy new: $17.16 / Used from: $15.19
Introduction to Schenkerian Analysis: Form and Content in Tonal MusicIntroduction to Schenkerian Analysis: Form and Content in Tonal Music by Allen Forte
Buy new: $45.70 / Used from: $17.49
Anthology of Musical FormsAnthology of Musical Forms by Leon Stein
Buy new: $18.95 / Used from: $7.75
Analyzing Atonal Music: Pitch-Class Set Theory and Its Contexts (Eastman Studies in Music)Analyzing Atonal Music: Pitch-Class Set Theory and Its Contexts (Eastman Studies in Music) by Michiel Schuijer
Buy new: $90.00 / Used from: $106.73
Anthology for Musical AnalysisAnthology for Musical Analysis by Charles/ Rothstein, William Burkhart
Buy used from: $10.00
Counterpoint (4th Edition)Counterpoint (4th Edition) by Kent Kennan
Buy new: $102.91 / Used from: $61.35
One of the better books on the subject that I've found.
WorkbookWorkbook by Kent Kennan
Buy new: $40.00 / Used from: $35.00
To be used in conjunction with the above.
A Practical Approach to Eighteenth-Century CounterpointA Practical Approach to Eighteenth-Century Counterpoint by Robert Gauldin
Buy new: $42.85 / Used from: $20.88
Also not a bad book on the subject, though some knowledge of linear/Schenkerian analysis is assumed.
The Study of FugueThe Study of Fugue by Alfred Mann
Buy new: $10.85 / Used from: $6.86
The Art of Fugue: Bach Fugues for Keyboard, 1715-1750The Art of Fugue: Bach Fugues for Keyboard, 1715-1750 by Joseph Kerman
Buy new: $14.49 / Used from: $9.95
Bach and the Patterns of InventionBach and the Patterns of Invention by Laurence Dreyfus
Buy new: $23.40 / Used from: $25.78
Study of Orchestration, Third EditionStudy of Orchestration, Third Edition by Samuel Adler
Buy new: $74.20 / Used from: $61.99
Treatise on InstrumentationTreatise on Instrumentation by Hector Berlioz
Buy new: $17.79 / Used from: $11.79
Anatomy of the OrchestraAnatomy of the Orchestra by Norman Del Mar
Buy new: $21.90 / Used from: $14.95
The Grammar of Conducting: A Comprehensive Guide to Baton Technique and InterpretationThe Grammar of Conducting: A Comprehensive Guide to Baton Technique and Interpretation by Max Rudolf
Buy new: $88.67 / Used from: $82.06
Some of the patterns seem questionable, but I have found the book to be useful anyway.
Preparatory Exercises in Score Reading (Vorbereitende Ubungen im Partiturlesen)Preparatory Exercises in Score Reading (Vorbereitende Ubungen im Partiturlesen) by R.O. Morris
Buy new: $24.28 / Used from: $14.98
Geared more towards pianists and conductors.
Accompanying Skills for PianistsAccompanying Skills for Pianists by Deon Nielsen Price
Buy used from: $24.95
Worth reading, and using, if you plan on accompanying. I don't agree with everything here, but I still recommend it.
Abby Whiteside on Piano Playing : Indispensables of Piano Playing - Mastering the Chopin Etudes and Other EssaysAbby Whiteside on Piano Playing : Indispensables of Piano Playing - Mastering the Chopin Etudes and Other Essays by Abby Whiteside
Buy used from: $87.93
Directed strongly towards pianists; however, this is one of the best books on this list, in my opinion.
A History of Keyboard Literature: Music for the Piano and Its ForerunnersA History of Keyboard Literature: Music for the Piano and Its Forerunners by Stewart Gordon
Buy new: $88.67 / Used from: $84.00
The Great Pianists: From Mozart to the PresentThe Great Pianists: From Mozart to the Present by Harold C. Schonberg
Buy new: $12.92 / Used from: $4.00
The Lives of the Great ComposersThe Lives of the Great Composers by Harold C. Schonberg
Buy new: $23.10 / Used from: $10.99
The Rest Is Noise: Listening to the Twentieth CenturyThe Rest Is Noise: Listening to the Twentieth Century by Alex Ross
Buy new: $12.24 / Used from: $5.44
100 Great Operas And Their Stories: Act-By-Act Synopses100 Great Operas And Their Stories: Act-By-Act Synopses by Henry W. Simon
Buy new: $11.53 / Used from: $0.01