Unfortunately, there is no way a new lender is going to finance a home with negative equity regardless of how good your credit is. Your best bet is to contact the bank you have your note with and try to work something out with them.
Many lenders are working with borrowers these days to keep them from going to foreclosure. If the rate goes up and you can't make the payments and the lender has a lot of equity in the property, they are in a much more favorable position and are less likely to work with you.
However, since there's negative equity, they might work something out, because it does them no good to incur the loss of all that interest that you could be paying and have it sold at sheriff's sale at a major loss on top of that. That's really your only option here. It may or may not work, but it's certainly worth the shot.