I use the following way to make packages of ukmp on OSX. So, this should be easy to implement on linux as well and it should be relatively easy to even make a GUI packager out of this (although I don't have the time to do it at the moment).

Make a install folder Let's call it: UKMPINSTALL.
Create inside of it the directory structure you need as if you would just be extracting a zip to the root directory of your device.
For example, add UKMPINSTALL/usr/bin. (and of course you want to have /usr/share/pixmaps and so on.
Add also a directory DEBIAN in the UKMPINSTALL.
To debian, add the files: changelog, control, copyright, postinst, prerm and rules. The usual debian stuff.
Then you can just call
dpkg -b UKMPINSTALL test.deb

I also have a small setup script that copies my latest versions of file to my install folders and then removes the hidden files created by OSX on each directory.

Also, the comment on not being able to build on windows is really true. On the other hand for theme maker I built the debian packaging from scratch in java so that it would work on windows as well (I actually had windows only at that time). That is also the reason why it's not working on n800 at the moment. I used standard tar library to make the data and control tar files, but for some reason standard tar support was dropped from n800 core libraries (actually from upstream, but that's beside the point).