My house has an underwater mortgage

I purchased my home on August 25, 2006 for $640,000.  It's a townhouse in California. Today it's estimated value on zillow.com is $402,000. This is surreal. My 1st loan is an interest only 5/1 arm @ 6% for $512,000. The 2nd is $96,000 30 year fixed @ 8.25%. My plan was to refinance before the first matured at a higher rate. That is no longer a viable option, even with flawless credit. So what are my options? I have 32 months till my situation no longer works for me. What should I do? Looking for help!