Did them myself, well my brother had the gear for doing it.
Its just a chemical that strips a layer off the glass. Then print whatever you want onto ordinary paper and cut out the template.
So, in this case, the bigger and more basic the lettering the better. Stick the paper template to the glass (think we used pritt stick) and then lash this chemical on over the gaps. Wash it off (only takes a couple of minutes to work) and you immediately see the frosted effect.
Cant remember the name of the chemical, i'll give the brother a text, but i know he got it on-line and there were some issues about some other places not posting it.
Takes a while cos you have to do a template for each glass (unless you use vinyl instead of paper) but the results are good.
