Emails written from within Yahoo Answers - where do they go ?

All emails go to your (and their) inbox of the registered email you (and they) gave when they signed up for Yahoo Answers. Just like the Best Answer emails and violation notice emails. The danger may be that they CAN accidentally go to the SPAM/BULK folder, so if you are expecting something and not getting it, always check there as well. Then, open and mark it as NOT SPAM so it does not continue to go there in the future.