There is not a single product that meets all your requirements. You are more likely to find 3 products that cover your 3 requirements, but in all likelyhood, violate your 4th requirement in the process. Having said that...
For storage management of your entire storage enterprise, there are the following tools. To the best of my knowledge, these all have Netapp support. You should also look at Netapp's native tools as well.
1. HP Storage Essentials (Formely AppIQ)
2. Symantec Command Central (Formerly Veritas Command Central)
Both of these tools are very slick and have tons of management and reporting capabilities, but they are not cheap.
To identify your duplicate files, CA (Computer Associates) makes products that can help with this. I've never deployed the product myself so I can't remember the name, but the demo they came onsite to give us looked quite interesting.
To do data migration in NAS environments (I assume you're referring to NAS since you mentioned Netapp) you should at Netapp's TOPIO and VFM products. There is also Sepaton, Acopia, EMC's Rainfinity, Symantec / Veritas, CA and Softek.
Take a look at this article for a list of vendors and products available:
<i>Data migration tools
Stephen J. Bigelow
To choose the right data migration tool you'll have to understand the
issues involved in any tiered storage acquisition, then evaluate
transparency, interoperability with storage systems and data,
complexity, retention and compliance regulations, policy enforcement
and other factors.</i>