The only experience I have this was for GUI interfaces not web pages, but we found very quickly that it was better to use a separate resource (the GUI equivalent of a template) for each language, than lots of individual strings. The problem being that saying the same thing in different langauges can mean the length of the strings vary enormously, which makes layout a pain.

It's probably less of a pain with web pages as HTML is more flexible, but there are other considerations too. Eg. Different countries perceive colors differently according to their cultural references. I can't remember which, but one country had a real problem with there being any red on a page. It was far easier to accommodate such preferences by having a separate template for each.

The only other piece of advice I'd offer is that you get your translations done by one native speaker and verified by another independant native speaker. We had some done by a second language translator and the results were more than a little embarassing.