OK I have solved my problem.
I was sure I had set all the right options in kernel config but obviously not... You may have the same problem too Darren. In between the "make mrproper" and "make xconfig" parts of the compilation process, you should copy /boot/config-2* into the /usr/src/linux directory. That will mean that when you do the config part it will use the settings from the previous kernel. When you choose options, change NOTHING but your processor type (eg I changed mine to i686 from 386) and add your soundcard.
That way there is no danger of you missing the module you need for networking.
In short if you have done what I did, you missed comiling in an important networking part, so use the defaults to start with and change only what you need to.
