I get a few emails offering to sell me domains, especially ones that are similar to domains that I already own. Thankfully GMail's spam filter tosses most of them into the junk mail folder so I never see them, the ones that do end up in my inbox get tagged as spam.
Now, if someone took the time to learn a little about my business and wrote a personalised email to _me_, not the email address in my whois, offering to sell a relevant domain and not just a ccTLD version of an existing domain I own, then I might take a bit more notice.