My area, like many, is very competitive. We have about 1 opening for every 50 qualified candidates. :-(
Don't give up hope.... My best advice would be to initiate contact directly with principals, rather than just relying on HR offices. After you submit your applications, send a letter of interest (and a copy of your resume) directly to the principals of the schools you want to work at. This way, the principal can specifically request your application when it comes time to interview.
Another piece of advice -- send lots, and lots, and lots of applications out. You may have already done this, but people who live in competitive markets that only send out a few are far less likely to get called in for an interview.
I know of an eBook that may help you also. It's Guide to Getting the Teaching Job of Your Dreams. It has lots of down-to-earth advice and info about finding teachig jobs, applications, resumes, and cover letters, as well as interview tips, and how to answer the most common teacher interview questions. Maybe the book can help you. It's at: http://www.iwantateachingjob.com
Best of luck to you on your job search! Don't give up-- the reward will be worth it.