You are number 11 at Yahoo for that term in quotes. Perhaps you need a little push to make it onto page one. It appears that the term is being pulled from your Meta Description (or the Keywords).
You are #47 for bee extermination (without quotes). This is probably because that is how it appears in the content of your page. I would rework the content and try to work in both words (exterminator/extermination) in some manner.
I looked at this page
http://www.locate-contractor.com/exterminator.html which is where you mention "bee extermination" (not exterminator). Although you have it in your keyword and description metas, you do not have it in your Title for the page.
A check for anchor text links with
"bee exterminator" does not turn up any links pointing to your page.
If you want to hit well for that term, you will need some inbound anchor text links to that page with the term in it. At least some links on your site will help.
One thing I have seen sites of this type do is provide an alphabetical index of services with links to the internal pages. On this list you can cover every possible term you can think of. It will also be good for your visitors to find specific contractors.