Reading Assignments, and other reference material.
The principal text is B&T, although much of the more technical material and details has been excluded. Page reference are to B&T volume 1.
S&G is useful, although their treatment is largely derived from B&T.
Given her speciality, Elmergreen's text has also been helpful in understanding epicyclic motion and resonances in disks.
Another excellent source is Josh Barnes's lecture notes.
Finally, the articles in EAA by Binney (Dynamics) and Saslaw (Stellar Dynamics) give good overviews.
Primary references: Broken down by topic :
Basics: B&T 103-108; S&G 95-103
Oort's constants: EA&C 2.4; B&M 637-642.
Epicycles : B&T 114-115, 120-125; S&G 116-121
Resonances : B&T 146-152, 351; S&G 209-211
Density Waves : B&T 336-354, 383-398; S&G 209-211.
Disk instabilities, Swing amplification & Bars : B&T 362-364, 371-383, 399-402; S&G 212-216. Barnes Ch 17, 18, 19.