Audit

In my oinion you dont requid any classes or coaching for either audit or  it-sa.Look whether you join classes or not you have to yourself study & uderstand the therory within so why waste time n money for tht.Better buy a ref.book n study together wid Practice Mannul & RTP issued by ICAI.

 Reference Book

Audit- Surbhi Banshal

IT-SM- Paduka (for Sm use module)

completely agreed with mohit u may refer paduka for company audit purpose 

surbhi bansal for audit.... 

According to me the module of the Institute is the best way to study.  Also refer teh previous years suggseted/compilations as the examiners set their questions based on the previous years papers especially for Ethics & the theory questions & all this will be more than sufficient for you to study Audit.