> esp0 at sbus0 slot 0 offset 0x800000 pri 3: ESP100 25 MHz, target 7
> scsibus0 at esp0
> error... error... (hung)
> There is an 'error...' text in the esp driver.

This indicates that your machine has some problems with the current
device driver. To get you started initially, there is a kernel
on theos.com:/pub/netbsd?.gz -- I update them every few days.

> I have asked Theo DeRaadt, but he seems a very busy person.

I don't remember receiving any mail from you, but it is possible.
I just got back from a few fun/business trips around the world..

Good luck -- get the kernel, then you shouldn't have too many
problems getting your userland environment up and running.
Mail me if you have any problems.