Including your email address can be a bad thing or a good thing. While it makes it easier to communicate and solves the question of paying for return postage, sometimes the information is not as good. Instead of sending you hard copy of records, you might receive a summary of the information on the records. Other times (and this has happened to me), you’ll get an email saying the person can’t find anything, even though you know for sure t here’s something out there. It’s easier to write someone off via email than international snail mail, I suppose.