Anything recent should work. There are tons of NIC brands, but few underlying chipset brands. So you find out the underlying chipset brand and download the drivers directly from the chipset mfg.
I've run gigabit NICs with Intel, Marvell, Realtek, Broadcom and nVIDIA chipsets under x64. I'd recommend Intel for PCI GbE. If you don't need GbE performance or can live with high CPU utilization, a Realtek-based NIC might be a better choice for pricing and availability.