I've exactly the same NIC (Intel PWLA8391GT) and it is showing from lspci as
and it's working fine - no additional drivers / config was needed.
06:00.0 Ethernet controller: Intel Corporation 82541PI Gigabit Ethernet Controller (rev 05)
If it's not giving the correct info from ifconfig (i.e. can't even work out if a cable is connected) I'd suggest taking it back to the shop and swapping it over... unless of course it's working fine in Windows / another PC.
Plus I'm assuming it's plugged into a 1GB switch... otherwise the orange light on the back would indicate a hardware / cable problem (brand new cable so probably not).
Just as a side note we use these cards a lot at work and have a fair few linux / Ubuntu boxes and the don't have any special config on the NIC... which makes me think it might be a duff one.