Hey Paul,

Linux Audio User is probably a more appropriate place to ask, as your question isn't really Ardour specific.

Do you need low-latencies? If your *only* recording live gigs, then you can get away with huge latencies no problem...
If you want low-latency 8 channel I/O, you're pretty much going to have to stay away from USB gear, there isn't enough bandwidth there to provide high sample-rate multiple channel audio.

I will advise the PCMCIA / ExpressCard route with a firewire soundcard. My experiences with the Echo cards is fantastic, and they have an 8 channel-with pre's unit. Its definatly *not* budget though...
http://www.echoaudio.com/Products/FireWire/AudioFirePre8/index.php

Good luck, -Harry

PS: Took the liberty to also sent this to the LAU list

On Fri, Sep 30, 2011 at 4:21 PM, Paul Winkler <slinkp@gmail.com> wrote:
I want at least 8 preamps built-in (convenience and cost trumps
quality for me).

Is there any such device?  I think there are some USB2 devices on the
market, but do we have drivers for any of them?

Or could I get a firewire PC card?