Jean-Marc,
I would request more information before I begin to give you an answer. What kind of computer are you using this on? Laptop or Desktop? Do you want Firewire or USB? If you don't have a Firewire port, you're going to need to get a card to use that. If you do, does it have the correct chip set for audio?

As Josie asked, do you want a stereo pair input, or multiple inputs. The more inputs, the more expensive it is. Do you want a MIDI capability?

For basic USB connection with stereo in and out, I recommend this:

http://www.pgmusic.com/ua1g.htm

Gary

I'm blessed watching God do what He does best. I've had a few rough years, and I'm still not back to where I want to be, but I'm on the way and things are looking far better now than what they were!