Over the weekend I rewrote the way supermin appliance building works to make it much more lightweight and mostly distro-independent. As a result, libguestfs now builds from source reasonably simply on both Debian and Ubuntu.
I’m also able to make binaries available for Debian and Ubuntu (10.10), but you must read the README file first.
If these do/don’t work for you, please let me know.
Richard WM Jones 
Not sure how these are supposed to be usable on standard debian lenny. The debs bomb out with dependancies on packages from sid. Is there a complete list of required deps from sid to make libguestfs function?
after 5 manual fetches of deps from sid I gave up with this result:
http://ftp.us.debian.org/debian/pool/main/n/ncurses/libncurses5_5.7+20100313-4_amd64.deb
http://ftp.us.debian.org/debian/pool/main/r/readline6/libreadline6_6.1-3_amd64.deb
http://ftp.us.debian.org/debian/pool/main/h/hivex/libhivex0_1.2.2+git20100712-2_amd64.deb
http://ftp.us.debian.org/debian/pool/main/libx/libxml2/libxml2_2.7.8.dfsg-1_amd64.deb
dpkg: dependency problems prevent configuration of libguestfs0:
libguestfs0 depends on libpcre3 (>= 7.7); however:
Version of libpcre3 on system is 7.6-2.1.
libguestfs0 depends on qemu-system (>= 0.13); however:
Package qemu-system is not installed.
libguestfs0 depends on btrfs-tools; however:
Package btrfs-tools is not installed.
libguestfs0 depends on cryptsetup; however:
Package cryptsetup is not installed.
libguestfs0 depends on grub-pc; however:
Package grub-pc is not installed.
libguestfs0 depends on libaugeas0; however:
Package libaugeas0 is not installed.
libguestfs0 depends on ntfs-3g; however:
Package ntfs-3g is not installed.
libguestfs0 depends on ntfsprogs; however:
Package ntfsprogs is not installed.
libguestfs0 depends on reiserfsprogs; however:
Package reiserfsprogs is not installed.
libguestfs0 depends on xz-utils; however:
Package xz-utils is not installed.
libguestfs0 depends on zfs-fuse; however:
Package zfs-fuse is not installed.
libguestfs0 depends on jfsutils; however:
Package jfsutils is not installed.
libguestfs0 depends on scrub; however:
Package scrub is not installed.
libguestfs0 depends on zerofree; however:
Package zerofree is not installed.
You will need to enable the “unstable” and “experimental” repository. I have:
All the packages you need should be available in there.
Similarly for Ubuntu you need to enable the natty repo: