often it it depends on what kind of Ausbildung your friend wants to apply. What kind of profession he wants to study? Does he look for a Ausbildung in a Company or an Ausbilung in a school.... But both start very often in september (and others also in February) because the Berufsschule (who normally also people have to visit one or two times a week, when they study/learn in an company) starts then.
Your friend can get some Informations about Ausbildung and different ways of education in the "Berufsberatung": Berufsinformationszentrum (BIZ) Stuttgart
Agentur für Arbeit Stuttgart
E-Mail: stuttgart( at )arbeitsagentur.de
But if you can inform us, what kind of Ausbildung he wants to start, please write and may be, I can give you more information.,