Language schools in Baden:

AVS (Audiovisuelles Sprachinstitut)
Audiovisuelles Sprachinstitut
Rathausgasse 22 (the back of Rathausgasse - down the steps along the right hand side of Moser bakery)
5400 Baden
Tel. +41(0)56 222 35 35
Fax +41(0)56 222 74 19
http://www.sprachinstitut.ch

TLC (The Language Company)
Bahnhofstrasse 44 (on the right hand side on the way from the railway station towards Hotel Du Parc)
5400 Baden
T 056 205 51 78
F 056 205 63 83
http://www.tlclanguage.ch/5-0-kontakt.html

Klubschule Migros Baden
Nordhaus 3 (West side of the railway station, at the end of the bus stops - see www.nordhaus.ch for a picture of the building)
5400 Baden
Telefon 058 568 97 97
Telefax 058 568 97 98

I did an intensive German course at AVS and found it excellent, but their evening courses are only once a week.

I suggest you go and see each of them rather than do it by telephone or e-mail.