I've found that most buyers don't want to be bothered. I had one buyer who had all her eBay messages sent to an email address she did not monitor...she didn't want to be bothered!
Now, a few buyers, if they like what you offer, will Save you and keep track of what you offer. 40% of my sales currently are from repeat buyers...some of whom I have been selling to for years. Most of my repeat buyers are serious collectors - when they find a source they like, the tend to come back. Some will let me know what they are looking for, some do not. One of my more interesting customers collects Santa, another penguins, another States.
If you have a Store, you have a mailing list -- promote that in your listing template (so you don't have to remember to add it all the time) and get people to sign up. Then be sure you set your mailing list up to go out as frequently as possible.
Member-to-Member communications for the purpose of soliciting sales is not allowed and, if reported enough times, could get you suspended or banned. Like I said, a lot of folks just don't like to talk!
Hope I gave you some ideas of things you could do to help buyers remember to come back.
-Bob.
