Look at the programs directory, most programs can be translated. You're usually looking for a De.rc file, if it's missing, make a second copy of the En.rc file, and call it De.rc. Now translate the strings in the file. You then have to edit the header file, this may be another rc file. In can case you can find the file by running grep En.rc * in the programs directory. Open the file, and add #include "De.rc" in alphabetical order in the list of language rc files. Once you've done this, make a patch, so your work can be easily applied to the wine source tree, a howto is at http://www.winehq.com/site/sending_patches. Also note that quite a few dlls need translating too. The file may not always be En.rc, for example in dlls/commdlg it's called cdlg_En.rc Finally, one important thing is keeping the translations up to date, so you should update the translation every time there is a change in the english resource file. Don't forget to check that the existing translations are up to date and correct. Once you've done a patch, send it, in the email body or as an attachment, to wine-patches@winehq.com This should give you plenty of work for now :-)
Ivan.