I'm new to Linux also, but I know that Linux doesn't "Plug and Play" like
Windows does.
You need to run your hardware config utility to install the card. (Probably
something like XConfig).
This Red Hat install site may help:
http://www.redhat.com/docs/manuals/linux/RHL-7.2-Manual/install-guide/
My Fedora install plays very nicely with my Windows LAN after much similar
wrestling, especially with Samba.
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Hoping to connect my linux box to my lan, I installed a Linksys 10/100
Ethernet card in a PCI slot on the Intel AL440LX motherboard.  No led
lights illuminated to indicate power going to the card.

Given that this is running only linux (Red Hat 7.1) and no Windows, I have
no idea how to see anything.

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