debimg 0.0.2 has a new high speed dependency resolver and support for local repositories.
With these new features, debimg is now able to produce netinst images in less than 4 seconds.
BTW, you can easily build your own disk. Simply unpack the tarball, change the mirror to your one, and run ./debimg debimg.cfg. This should give you an i386 netinst disk.
Get debimg 0.0.2 from http://users.alioth.debian.org/~jak-guest/debimg_0.0.2.tar.gz
Fetch daily-built images at http://jak-linux.org/cdimage/daily-builds/testing/.
For more information, see http://lists.debian.org/debian-cd/2008/03/msg00114.html