Jason,
I can understand your frustration with regards to your situation. I don't think finding another LO or company to work with is a smart option, however. If you think this company is not playing by the rules or is really not working in your best interest then that's another story. Starting this process over with someone else is basically game over...start again at level 1. New appraisal, probably higher rates as of today, new paperwork, etc. Ultimately it might cost you more to start all over than to extend your lock for a couple of days/week.
Talk w/ your LO and make him explain EXACTLY what the situation is. Come back and post it and we can give you further advice as to the situation. But leaving them just because the lock expires is probably not the best option for you at this point.
Keep in mind, your LO WANTS to close your loan just as badly as you do. He doesn't get paid unless it closes. Find out why he can't close it and you might have a better feeling towards the situation.