Bookstore in Taibei for buying classics?

Hi there,
Since my year in Taiwan is slowly coming to an end I plan to take a trip to Taibei in order to buy some books. I recently learned Zhuyin, yet I fear that if I don’t practice it to some extend I will forget it again quickly. So I plan to buy one or two books with Zhuyin transliteration along with the chinese characters. Preferable some classics, especially buddhist texts are preferred. I’m sure there must be a lot of stores that offer this in Taibei. Anybody here has a suggestion where to start?
With best wishes,

raellear

Just as an aside - there are top notch zhuyin input methods for both android and iphone. That might help you remember.