Type Barnes and Noble in your search engine and you will be able to select their online store from a list.
I did it and there is Trigonometry for Dummies in stock
(Don't be offended It is just the way they use words today)
Dummies actually means beginners.Whats is a great book to help a beginner understand trigonometry , that Barns %26amp; Noble would have in stock?
Try trig for dummies, seriously I have used many "for dummies" books and they can sometimes give you the perspective you need.