I hope this message reaches you before you leave. First, read this Wiki page:
I recently updated this to include links to all the necessary forms and procedures. You would normally be able to enter for 3 months by using a fax or email, and extend your visa for another 3 months after arrival. However, if you don't have a means of support or money for a fare out you are unlikely to be allowed to enter at all. Working on a tourist visa isn't allowable in any country I can think of, and without knowledge of regulations and customs your plan to hunt and fish to stay alive may end you and Kristian up in jail - or at the very least, the recipient of a heavy fine and/or the ire of the locals.
Traveling with no backup plan is foolhardy in the extreme. Anyhow, since you're already planning to leave the US may I wish you the best of luck.
In short your best, and maybe ONLY, chance for entry is to prearrange a transit out before arrival. You MUST give 96 hours notice of arrival but not necessarily from home, it can be done in transit and will normally be done by the captain. Even then, since your travels don't consist of paid employment, you may have to provide a contact address and show means of support while waiting for your next ride.
Rob (aka Haiqu)