Creating bootable USB for Seagate GoFlex Home (no replies)

I have a Seagate GoFlex Home. I'd like to leave the internals mostly alone (just because), with that as a starting point.
I'd like to create a bootable USB with the latest supported debian build so that I can run a small fileserver with NFS exported directories.

Simple - right?.... <sigh>

at some point last night.. late.. (remember - never hack hardware after midnight... or feed gremlins... bad things happen....)

I had the system boot the thumbdrive ... once-ish... it had debian lenny,
I had started off with the load "wheezy" script, it failed (some kind of error about firmware too old or somesuch),
then I tried the dockstar squeeze script... it too failed - (same error)
then the lenny script... Success - - - However, I could not find a repo to add to the sources.list file that wouldn't generate errors...
so the system never updated.. I successfully booted several times, so I know that the internal pointers know about a bootable usb.
I then tried to re-run the wheezy script... and that messed up the thumb drive...

so back to square one...

so my main question is (I think) - how can I create the bootable USB on (for instance) my laptop (ubuntu 15.xx) ?
What source repos do I put into the sources.list file for the ARMEL foundation?

one tutorial says download the boot.img file from http://http.us.debian.org/debian/dists/stable/main/ and start from there...
there is no boot.img.gz file in the armel directory.... (or am I missing it?)

I think I have seen a tutorial on this topic - but I can't find it again...

Thoughts? Help? Directions?

Rich