You may get a manual from their site, or from them.
However this will be unlikely to be a manual on how to set up Telefonicas ADSL service, and it won't affect the instructions on the CD you have with it - to install the configuration programs, I don't think (unless they have an English option - the last one I saw didn't.).
If you really can't follow it, I suggest you engage the services of a local technician who is properly bi-lingual.
One important point when configuring the Telefonica service, is to choose correctly whether tio install is as "multipuesto" (multipoint) or "monopuesto" (single point). In multipuesto the rounter acts as a DHCP server, and supplies the DNS and IP information for several attached systems. Even if you're only attaching one system, multipuesto is probably the best choice, if you can make it with your contract.