Analog digital converters

I believe the Meridian 562 will fulfill your needs as an ADC. I have one that takes my analog sources and outputs them to digital. The 562 has been around a long time and since you don't need video switching, you can go with a regular (non-"V" version). They're not terribly expensive and are built like tanks.

What is your budget and what level of quality are you going to be happy with?
I use an E-MU 1616M soundcard (List $500) that has pretty good A/D conversion for doing Hi-Rez needledrops. I like it, although it has way more features than I need. I think the 1212M may be a good bang for the back as well and is a lot less money.

behringer makes an inexpensive a/d d/a that I use to digitize records. There are other units by m-audio as well as digital recorders with line in and out connections. Look in sweetwater catalog or guitar center online.

I use an M-Audio Audiophile USB outboard sound "card" that I found on eBay and paid well under $100 for. However I would love to have an Apogee Rosetta 200 one day, for well over ten times the price. In between, my choice would be an Apogee Mini-Me with USB.

Wadia makes a pair of units:

http://www.wadia.com/products/w130and150/130_150_home.htm