In my GCSE poetry anthology book there was a poem called Unrelated Incidents, which was written in Scottish Dialect.
Also, I can't remember whether Half Caste was written in Dialect or not, but it may be worth looking up.
I have tonnes of language stuff at home which I could look through- there'll probably be stuff on the theory side if you're interested. I also possibly have some of my work books from Eng Lang from Glasgow, which I could get to you if you wanted? (Though I have a nasty feeling I may have recently binned these). I definitely have a bunch of text books and stuff though, and probably have some notes from my A levels. AQA B should have some past papers featuring dialects which may or may not be excerpts from literature.
If it's any use, let me know.