There are some free online tools that will help you evaluate how well you've built your site. The best one I've found, so far, is the SEOmoz Term Target. Carry out the following steps to use the free page grading service from SEOmoz:
1. Go to http://www.seomoz.org/tools (you may need to register for a free account first). Click on the Term Target link. You should see something like this:
2. Put in your page's URL and a keyword (one keyword) and click on Grade My Term Targeting. You will need to wait for about 30 seconds and then see your grade, (as seen in the following sample) screenshot:
3. Anything less than an A needs more attention. Go through each of the recommendations listed and fix any issues with your site.