Here’s some info about Cain’s wife:
http://www.answersingenesis.org/articles/nab/who-was-cains-wife
And about Noah, although I don’t know if your question is addressed:
http://www.answersingenesis.org/home/area/faq/noah.asp
Noah’s kids were all adopted, So it was sorta ok.
LOL! That’s cute!