>Alta Vista offers translations of it search results, so if you get your page listed there you can use their feature.
This is a good product if you want to get the general idea of someone's site in another language or to translate an E-Mail you have received. But I would not rely on it for a translation of your site.
As Andrew stated, it depends on your market. I am planning to translate my firm's website into Spanish because we do a lot of international work. If you do it correctly, it should give you a boost over sites that are just in English.