My 'intranet' : IDing the PC's NIC

Sometimes, it doesn't matter. You have links on-board the card and all is clearly laid out. So you can set the IRQ and base address.
But, sometimes, it is necessary to configure the devices. ISA devices were not too heavy on the whole plug'n'play aspect, so you might encounter a device with no links that the system simply refuses to see.
What you need to do is look for any sort of identifying mark.

I was lucky. My NIC has a sticker saying "Kingston - NetWare ready". So I logged on to Kingston's website simply by 'guessing' www.kingston.com and looked for network cards.
Many were sold. I guessed, being an old ISA card, that it would be in the discontinued line.
But which one?
I noticed that many had a little application utility which could set up the NIC for the correct IRQ and base address. So I downloaded a couple and tried them on my system...

The first I tried was for AT/LANTIC (cute pun!) card, to set IRQ 3, base 0x300.
It choked for a moment, then told me no devices were found.

So I then tried for the EtheRx KNE2000, same settings.
IT WORKED!

So I went back to Kingston and downloaded the device drivers for the KNE2000.

It may sound a precarious affair, but I bought a bunch of different ISA network cards for a fiver. If that didn't come up as being something, I'd toss it and try another. If you are less willing to suck'n'see, then go buy one new. They are pretty cheap these days.

If you have bought/found a PCI network card for your machine, chances are it is some kind of plug'n'play device, and chances are Windows95 will recognise it.
You are, currently, on your own here though, as only Windows3.11 is described. I shall assume you are not running Windows for Workgroups 3.11 on a PCI capable machine. Talk about a sledgehammer to crack a nut!
That said, there is a nicely detailed but graphically intensive walkthrough available. I think it is for Windows ME, but much of it should still apply with Windows 9x users.