Did you mean an answer key for the chapter specific assignments? I don't believe that those exist. The key in the back of the book is only for the Optional Self-Tutorial which is still pretty useful. Textkit is actually a living
answer key ;D so if you choose to, you can use this forum to ask questions. The accompanying workbook is VERY easy, but may be a necessity since you are doing it on your own.
UPDATE: answer key is here http://www.textkit.com/greek-latin-foru ... hp?p=10356
flebile nescio quid queritur lyra, flebile lingua murmurat exanimis, respondent flebile ripae