See the file README.modules in the distribution for an example of how to get a PnP ethernet card running, using a loadable kernel module driver.
See also the Ethernet-HOWTO available from MetaLab website Ethernet-HOWTO or from TSX-11 ftpsite Ethernet-HOWTO, or from their respective mirrors.
If the network card supports jumperless mode (fix the card's configuration using a DOS program that comes with it), or has jumpers to disable PnP mode and configure the device; if PnP settings don't work, the simplest thing to do is to configure the card in jumperless (non PnP) mode, or using the jumpers, to a fixed address and interrupt (I use 0x340 and IRQ10).
In the BIOS, assign IRQ10 to legacy ISA. If you have other PnP devices
which require configuring, remember to add the network card resources
used to the /etc/isapnp.gone file.
Build the network driver as a module, then load it during bootup with commands such as (for my NE2000 clone for example):
# # And the network card # MODULESDIR="/usr/src/linux.`uname -r`.pf/modules" rm /modules ln -s $MODULESDIR /modules insmod $MODULESDIR/8390.o insmod $MODULESDIR/ne.o io=0x340
This method won't require isapnp to configure the network card (in fact, isapnp won't be able to see it).