Users who have emails turned off in their user settings ("Receive Email from Other Members") should probably have "Receive Email Notification of New Private Messages" turned on. We've been getting a steady stream of requests to forward message to members who don't accept emails and don't notice when they have a private message (PM). If you turn on email notifications of PMs we'd be off the hook for forwarding messages to you manually.
Please review these options in your user settings (see "Edit Options" under the "Messaging & Notification" section) and consider turning on either allowing emails directly or getting email notification of new PM's. Your email address is not revealed to the sender with either option.
The bulk of requests we're getting to forward messages are from people who have seemingly legitimate questions about a Wanted/For Sale item or a question about an archived post desiring further information. You can, of course, choose not to respond to these queries, but we'd just as soon be left out of the exchange.
If you have an item pending in Wanted/For Sale, you should probably be set up to accept emails from members. You can always turn it back off later. At minimum give contact instructions in your advertisement and be sure that method works.
Starting today, newly registered users will have "Receive Email Notification of New Private Messages" turned on by default. Users can still turn it off if they wish.