Sure, there's many out there. Creative even has a few on their newer cards, and most recent motherboards too. Asus has a fine one in the DX which I think is a step up from X-Fi all around. If you care about sound quality, the Asus can be a lower cost entry or you go with something like the HT Omega eClaro
. At the same time though; if you're searching for digital i/o, optical is just a connection concern. You could go HDMI and get the same result for example. A good analog connection to a great sound card is still the best of the best, but the wiring can get fussy.
I guess it all comes down to what you want out of this. If you just want an optical out, the choices are plenty. If you want good sound out of it, we need more info. I wouldn't hook any optical out to a good receiver unless it was critical to do so. Scott Wilkinson helped me a lot on this, and he's no newb.