If you’ve not used it before, the Term Extractor at SEOmoz is an eye-opening tool. You give it the URL of your page, and it tells you what search terms it thinks you’re trying to target.
As SEONoobs put it — “that way if you’re trying to target “garden tools” and the term extractor tells you that it thinks “sea monkey poop” is more SE targeted, that you have some work to do, keyword density wise!“.
I run this on all of my sites from time to time, just to make sure I’m not missing anything major, and I usually find a handful of small things to correct. I consider it one of the best free tools out there.