I'm not sure if this was answered already or not because there's so many replies. I noticed most missed on the point that you want a physical copy of the photograph, not just a digital one.

So what do you do? Simple.

Make a high quality scan of the photograph and take it to a pro printing lab. Do a quick search for pro printing labs near your home, I'm sure a few will appear.

In the case that you can't find one near you, you can always order prints by mail.

I've used idigital before and they are great. They also ship out the photos so you can order from anywhere in the US.. http://www.idigitalphotolab.com/Contact_us.html

Nations Photo Lab is another. I've never used them but have heard good things about them. http://www.nationsphotolab.com

On a last note, try to stay away from services the cater to the armature photographer, like Snapfish, if you are after high quality photographs.

Hope that helps!