Anyone tried the Google adwords placement performance report? When running a content campaign, you can see which publishers have been showing your ads.

Content campaigns have traditionally been approached with some caution. However, you could use this in order to refine you content network campaign by targeting relevant sites and using the site exclusion tool to block ads from being shown on less relevant sites.

Always ensure you track content traffic aside from search network campaigns to ensure your analytics data is more 'pure'