I ran across a couple of great tools on the web to help you with Hyper-V.  The first is a Solution Accelerator called VSA

Microsoft Virtualization Solution Accelerators

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  • Take advantage of Virtualization and Windows Server 2008 R2 Hyper-V technology to consolidate workloads, minimize operational costs, and maximize planning flexibility with the MAP Toolkit for Hyper-V.

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  • The Infrastructure Planning and Design (IPD) Guide Series provides concise planning guidance for Microsoft Virtualization solutions. Check out these Virtualization-focused IPD Guides:
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  • Elevate the security of virtualized Windows Server environments to address business-critical needs with the Hyper-V Security Guide.

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The other one is a excel spreadsheet written by Aidan Finn on his blog

he built this spreadsheet to look at RAM, Disk, Clustering and CPU needed for Hyper-V  interesting resource