Where is the password hash?

[Fritigern]

As far as I understand it, to crack a password I find its hash and then attack the hash in the most appropriate way, given what I know about the password.
Is there a resource that reveals the offset within the file of the password hash start and the algorithm used to hash the password?
For example, AES 256 disk image greated by OSX Mountain Lion? Or any other Apple dmg file?

Thanks

Frank