[AAR.oner]

numerous options out there for AD/DA conversion, guess it depends on yer budget and features yer lookin for...if all ya want is simple transfers via RCA/SPDIF i would personally go with an MAudio Audiophile 2496 -- *much* less issues that can arise with a dedicated PCI interface vs a FW/USB AI

but if yer set on USB unit, it *really* depends on yer budget...for the cheap end -- Presonus, MAudio, Roland/Edirol all have gear that'll do what yer lookin for [i used a Edirol UA5 for years, great piece of gear when on a budget]

if ya wanna move up a bit to more "studio quality" -- Focusrite, MOTU, SoundDevices