Normally I would have recommend this link --
http://www.digitalpoint.com/tools/suggestion/
but it doesn't seem to be working at the moment.
It normally compares Wordtracker results with Overture. At present, it is showing the Wordtracker results as "faultcode" -- perhaps a move by WT due to not having an agreement to have their database used freely by Digital Point, but I'm only speculating.
However, the idea is to find these types of tools to get an idea of search phrase popularity shown on a given daily basis. Wordtracker itself has a free demo you can try (wordtracker.com), which is based on MSN search results. Though not a comprehensive tool in demo form, it still gives you an idea of what's out there, and other plausible combinations. The paid version is worth the money and is much more comprehensive across the major search engines, imo.
But you're right, the search phrase you mentioned doesn't seem to have any substantial yield. A suggestion is to look for more densely searched combinations of keywords that would reflect your site, and optimize for those.
Hey, best of luck! Beat those spammers.