Hey man, sorry to hear about what happened. That really stinks!!
Although it doesn't help you much right now, I would recommend picking up a capture card for your PC and transferring all your tapes to CD or DVD. I did it with all my important stuff like wedding video, F1 race I went to, family movies, vacation stuff, etc... I have 2 copies of each so if anything ever happens to one of them, I still have another. Plus, the media will last a lot longer than the cassettes. I know the last thing you want to hear right now is how it could have been avoided, but if you have other valuable things on tape, I'd recommend the caputre card.
Here's the one I use (PCI) and I've been quite happy with it.
Was the video footage taped with a 8MM video cam? If so, you may still have the 8MM tape lying around somewhere. Might be worth a look and you can transfer it from there if you're lucky enough to find it.
Stryker