I basically only sell to the so called "end users" or at least I sell at the so called "end user prices"
Basically what hat I do is:
1) Look for simillar domains and extensions & Conduct searches in SEs for related websites.
2) With this I compile a Email list of potential interest buyers (based on website or WHOIS contacts).
3) Then I set the name on auction (no FSBO).
4) Right after setting up the domain auction I send out a mail to each identified potential buyer, and inform them about the auction.
(1 by 1 and personalized for each buyer)
Important in my experience is, that if you want to attend a decent sales price is to set up the auction BEFORE you mail the potential buyers. This has the effect, that it puts indirect pressue on buyers (bid now or you never have a chance again)
A FSBO mail to a potential buyer has not much effect, or you just receive a bunch of real low offers.
PS:
It is advisable, to evaluate trademark conflicts before you send mails
