Relatively speaking, the $8,000 shortfall on your current home is not too bad. The Visa debt is another story and one that won't get better unless you can make over the minimum payment contributions.
Without a job and bad credit, you'd have a hard time finding a refinance option. But, check http://www.makinghomeaffordable.gov to see if there might be a program specific to your situation.
I would also strongly suggest you consider selling the lots. There's an asset that could help you better your situation.
Better Homes & Gardens Real Estate Metro Brokers