Exchange 2003 to 2010 Migration

Hi,

I am sorry if someone has already asked this question before but we will be transition/migrating from exchange 2003 to 2010 - we also want to include DAG option in our setup.  

So we have one exchange 2003 server and will be building another exchange 2010. Is there any document  or video or any sort of guide i should follow to complete this task.

Thanks