Tom is right, but you must also decide what youy want your internal auditors to audit.
Many companies keep internal auditors restricterd (if restricted is the proper word) to verifying/validating procedures, WIs, etc. and do not want them interpreting ISO9001 or QS9000. This is discussed in other threads here at length - my recommendation is to leave ISO and QS interpretation to the managment representative or other qualified person(s).