German friends tell me that looking for German/Austrian medieval sources of that period is a hopeless quest since so much material was destroyed during WW2 - much of their research relies on English and French sources.
I am not aware of any surviving 11th century sources on looms from those areas, but there is the much older (Carolingian) Utrecht Psalter from the Metz area of France. This book was originally produced in the 9th century and in around 1000 it was "borrowed for copying" by the monks of Canterbury, where it remained for over 600 years (the library fine must have been huge
It includes this image of a vertical loom:
The same image was copied into the Eadwine Psalter of about 1155 by the Canterbury scribe Eadwine (although with added colour and finer detail) and it looks as if this type of loom was still familiar at that time.
This type of loom was certainly known in 11th century Italy:
This is a miniature from the manuscript De universo
by Rabano Mauro, Italy 11th Century and produced at Montecassino - now held in the British Library collection.
I am aware of recent work in Holland which looks at textile production; try to track down "An evaluation of textile production, Journal of Archaeology in the Low Countries 2-1 (May 2010)" which may be available online. I believe there is some useful stuff on early medieval looms which would also apply to Germany at that time.
Edit: I found the document as a .pdf file here:http://www.jalc.nl/cgi/t/text/get-pdffb ... no=0201a02