@paul79
social connections, building relationships with seasoned domainers and getting your name out there as someone who is an active member of this online society of investors.
Twitter connection building for one; this can be a gold mine if you invest the time into networking, focus on following any and every person whom is on twitter for the sole purpose of domain networking(also but not limited to: website dev's, logo maker's, registrars etc)
If a tree falls in the woods , without a soul for it to be heard, there was surely a noise but no one noticed.
Recommended sites to set your domain(s) on for exposure to begin with:
1.) Sedo.com - If you havn't already, i suggest making a sedo account and adding your domain(s) to build a profile. This will allow someone seeking for your domain to actually find it by search if it is of the exact nature to which the user is seeking.
2.)Godaddy.com - Sign up for a year of their auction membership and put your domain(s) on their auction system.
3.)Afternic.com - ^ same as above
4.)4.cn - Largest chinese domain selling market place. This is a little more difficult if you're not Chinese/speak it and/or don't know how to have pages translated. But again, this returns back to the whole networking with domainers theory. Surely you will make a contact whom deals with Brokering to Chinese sellers, which is a shoe-in to that market.
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This is all opinionated of course, but from what I have learned, I felt this would be a good starting template to start from to get your domain(s) out into the online world of domainers.
--Chris D.