Many of the self-help books that I recommend on this website include sections on cognitive reappraisal. Perhaps the best single source that focused on cognitive reappraisal in detail is the following highly regarded self-help book:
Greenberger, D., & Padesky, C. A. (2015). Mind Over Mood, Second Edition: Change How You Feel by Changing the Way You Think. The Guilford Press.
The authors have an excellent website to accompany the book.