I am looking for detailled resources for Trachtenberg and his
Mathematical Institute

ref: http://en.wikipedia.org/wiki/Jakow_Trachtenberg

Some of Trachtenberg's publications are mentioned in the online
catalogue ("Helveticat") of the Swiss National Library:
http://topaz.snl.ch/cgi-bin/gw_44_5/chameleon?skin=helveticat&lng=en

Entering "trachtenberg" as search term you'll receive a list of 18
items. Two of these (4 and 11) mention an address:
Zürich, Hochstr. 36

Items 11 and 12 refer to the district within Zürich, i.e. "Zürich 44"
(today's postcode is 8044).

Based on these catalogue entries I have the impression that "Zürich
44, Hochstrasse 44" was the address (at least for some time) of
Trachtenbergs institute.

You can find out where Hochstrasse is located by using this map:
http://www.stadtplan.stadt-zuerich.ch/stadtplan_beta/Stadtplan.aspx

I do not know if the current buildung "Hochstrasse 36" is the same as
approx. 55 years ago.

Perhaps the local archives ("Stadtarchiv Zürich", i.e. not
"Staatsarchiv") will be able to provide further details:
http://www.stadt-zuerich.ch/internet/stadtarchiv/home/kontakt.html

There was a book published in the US (and perhaps elsewhere, too)in
the 60s called (from memory) The Trachtenberg Speed System of Basic
Mathematics.   It was popular enough at the time that you should be
able to find it in a good library, or perhaps on eBay, if it sounds
like it's of interest.