After years of procrastination, I've finally added a Contact Me form for anyone who wishes to contact me privately rather than post a comment.
I'm using Kontactr, we'll see how that goes. So far it seems acceptable. It does append an ad to the email, but since that only goes to me, I can live with it.
The form requires that you enter an email address, but it does not have to be a real one. If you don't want to include your email, use something like "firstname.lastname@example.org".