Oscar, there is a section on ebay, that you can "request customer address" and in fact ebay gives it to u automatically within a few minutes via your normal ebay page etc.

When I used to sell alot of stuff on ebay, if a buyer had met certain criteria (mainly that they had won an item from you) you could easily obtain their registered ebay address and phone numbers etc via a link similar to the dispute reoloution link.

This way, you can get the real details, or the details listed at least, forthe smartass people who are stuffing you around.
Then, I reckon you can name and shame them on here at least (subject to moderator approval) for dicking you around.

Perhaps, it may be worth while you "farming a few machines out" to friends or family to list so that the ads appear like any normal random one off ebay machine seller. It will be hard for a certain individual, or individuals, to then target all your listings.

Hope it helps.