Dunwoody Press has published my Introductory Coptic Reader: Extracts from the Gospel of Thomas with Full Grammatical Explanations, containing 40 extracts from the Coptic language Gospel of Thomas.
Here are some on-line aids I've made for learning Coptic.
Outlines of Coptic Grammar (PDF files)My [unorthodox] thoughts on Coptic pronunciation
A short classified vocabulary of Sahidic together with example sentences (PDF file)