If you're listing domains on popular marketplaces and think they're getting a bunch of exposure then you're probably wrong. Marketplaces (like Sedo, Afternic..etc) have hundreds of thousands of listings and your domains are probably getting very little exposure that way. At the very least, make sure you've enabled Sedo MLS and Afternic Fast-transfer so you're names will show up if people type them into a domain search at registrars which partner with those marketplaces. You probably stand a better chance at someone visiting GoDaddy and typing in your domain, seeing it's listed for sale, and then buying it as opposed to having someone find it on one of the big marketplaces.
But, to answer your question, aside from listing it on domain marketplaces there are dozens of other ways to get your name out there. Let me list a few that quickly come to mind...
1) Google. Visit the search engine and type your domains term in. Find good potential buyers with really similar domains and send them a friendly email to see if they're interested. In fact, there's a whole thread dedicated to this topic
right here and it's got plenty of pages for you to go through.
2) Social Media. Why not share your domains on some of the popular social media sites? Create a twitter dedicated to posting your names with hashtags, post into domain-related Facebook groups (there are tons of them), post into domain-related LinkedIn groups (there are tons of them)...
3) Forums. Why limit yourself to only posting your domain listings in the
External Domain and Website Sales section of NamePros? There are other forums out there you can find and list on as well. Just use Google!
4)
Dotdb (not my site). A great free tool that will let you see what other similar domains are currently registered. For example, if I owned the domain ShoeBox.com I could visit Dotdb and just type in Shoebox with no spaces or extension, and now I'm presented with pages and pages of domains registered with the term "shoebox" in them.
Hopefully that will give you some ideas and keep you busy for a while
