It may be a good idea to try to sniff out users' locations using a script to find their domains. However, this will not always be reliable, as that language may not be viewers' primary language or language of choice. A useful addition to your site would be a list of translation tools available for your visitors to use. Try it out for yourself and evaluate the results. I think it's very impressive.
Cultural awareness is another important factor to take into account.
Yvonne Cleary of the University of Limerick, Ireland has written a paper concerning the impact of cultural issues on the usability of a localised web site. It's clear that language is only one consideration when designing international web sites. Presentation, navigation, quantity and quality of information are amongst the other things to take into account. Try to understand your audience as best possible. Don't be afraid to solicit suggestions or strike up business partnerships to help you better serve a community that is unfamiliar to you.