Where is sasl config

[Florian Lindner <mailinglists@xgm.de>]

Hello,
I have just installed libsasl2-modules-sql with dependancies to enable postfix 
to authenticate users for SMTP relay. Now I'm looking for the config files 
for the SASL lib but I can't find it... Where is it? And how could I have 
found out myself? (e.g. print all files an package has installed)

Thanks,

Florian