How can I find more jobs to apply to?

I live in Michigan and we have the highest unemployment rate and the least amount of jobs. I log onto Careerbuilder, Monster, and Hot Jobs daily. I also have pulled lists off of Hoover's, Forbes, etc. to use as a guide. I then apply via the company website. I have received calls and a few interviews but the competition is stiff. The feedback I am getting is that available positions with my expertise and qualifications - the recruiters are receiving between 400-600 resumes minimum. How can I make myself stand out? My resume and cover letter are good, and I think my interview skills are pretty good, too. I just haven't had enough open positions to apply to and therefore, "close the deal". It's so frustrating. Are there any other job boards out there, or is there something else I should be doing? I feel like it is really a numbers gain. The more positions I apply for - the better my chances. Any ideas?? I am getting so frustrated. :(