almost every mirror has these bootdiscs. For example on my favourite mirror:
ftp://ftp.nl.uu.net/
in the directory /pub5/suse/i386/9.3/boot/ is a boot.iso file of about 50 MB. Download and burn it, but first write down the mirror! also write the whole directory path towards the 9.3 directory down...
Now when you boot from the CD, You just follow the steps to the installation, and when Suse asks for your installation soure, choose ftp and setup your Internet Account.
Then it asks for a IP adres from the source server. You don't have to fill in a specific ip, you can also just fill in ftp.nl.uu.net for example

But it also asks for a directory. You have to point the installer to the /pub5/suse/i386/ directory if I remember correctly, and not to /pub/suse/i386/9.3 You just have to try out a bit between the different directories towards the 9.3 dir.
After that just follow onscreen instructions
