To locate books about a specific person or topic, use the Subject Search in the OPAL Library Catalog. Each book has been tagged with specific subject headings that describe its content.

A wide variety of subject headings are useful in locating materials related to Music Theory.
Use the following subject headings as examples:
Most books related to Music Theory will be found in the MT collection which is located in the moveable shelving behind the reference desk.
| MT 5.5 - 7 | Music Theory - Instruction & Study |
| MT 9 - 15 | Printed pedagogical aids |
| MT 20 - 34 | Systems and methods (e.g. Dalcroze) |
| MT 35 - 39 | Ear training / Notation |
| MT 40 - 67 | Composition. Elements & techniques of music |
| MT 50 | Harmony textbooks |
| MT 70 - 74 | Instrumentation and orchestration |
| MT 75 | Interpretation |
| MT 80 | Embellishment |
| MT 90 - 146 | Analysis and appreciation of musical works |
| MT 165 | Tuning |
| MT 224 | Keyboard harmony |
| MT 870 | Sight Singing |