No problem - it was pretty self explanatory.
I initially tried the i686 download, but it didn't like my machine, complaining that certain libraries weren't built with the glibc2.2 (Debian Potato is based on glibc2.1, I believe). But I found binaries under the 'linux' folder which worked - ftp://ftp.cdrom.com/pub/ImageMag ick/linux/glibc-2.1/i386/ImageMagick-5.2.5-1.i386.tgz
Debian places everything in /usr/X11R6/ instead of /usr, so I did that, and then I just had to make a few symbolic links from /usr over to /usr/X11R6 cuz the ImageMagick binaries were still looking in /usr.
Now, to dig up all those picture CDs that I have lying around the apartment...