Internet research, finding addresses

I require someone with a few hours to spare, internet access (and ability to search the internet) and, preferably but not compulsorily, an understanding of German. What I need are contact details (contact person name, address, email address and URL) for all tourist information offices/tourism authorities in cities and major towns across Germany, Austria and German-speaking Switzerland. It might be helpful to work from a map. It would be ideal if you could insert the information into an Excel sheet, preferably arranged alphabetical by city, to make it easier to read. This is just a one-off task for which I'll pay £20 per hour to a maximum of 5 hours. Please keep a note of how long it takes.
Many thanks.