There are more excellent sites to come (somewhat) at grips with the difficult Sütterlin and
Frakturschrift [Black Letter] used in original German and Austro-hungarian documents.
Alte deutsche Schriften
also in English language version!
Deutsche Schreibschrift Klaus Düring
you can even install the Sütterlin fonts on a Windows PC - unfortunately I have not seen it for a Mac till now
There was an online course in Sütterlin made available by one of the Universities in Germany, but I could not find it again.
Cheers
Kees