You could try a prox_y (google should be able to provide a lot of FAQ's), but no guarantee that it'll work without any problems.
It sucks that german pay tv channel Premiere having the rights, prevents german fans from buying the Wimbledon streams. It's not like they'll stream all those courts themselves.
French and Italians fans, for example, will be able to use the official streams, although the matches are also only shown on pay tv in their countries..
Well, as usual, there should be many free stream alternatives.