I usually recommend PrintArt to my customers, they offer decent quality prints on canvas, aluminum, regular or fine art paper prints, with or without framing. You can do it all online. Great customer service as well.
Here is the address: http://alinemarandet.printart.ch/pro...shop/index.php
. Just scroll towards the bottom of the page and click 'eigenes Bild hochladen' to load your own picture. Only downside is, the website is only in German. If that was to be a problem, call customer service, chances are they do speak English