Can I deploy AX 2009 in a virtual environment?

Yes, AX 2009 can be deployed in a virtual environment.   Microsoft Dynamics AX 2009 is certified on Windows Server 2008 with Hyper-V Virtualization, and will support other virtualization solutions participating in the Server Virtualization Validation Program, consistent with the guidelines listed for all Microsoft software as part of Knowledge Base article http://support.microsoft.com/kb/897615

If so, how?

When deploying AX 2009 in a virtual environment there are no specific variation between a physical installation and a virtual installation.  The most commonly referenced 'how-to' guides are the AX 2009 Implementation Guide and the AX 2009 Installation guide.  Here are two resources to review prior to beginning your deployment:

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AX 2009 Implementation Guide - http://www.microsoft.com/downloads/details.aspx?FamilyID=466c7165-4349-4903-8717-27c924b6f58a&DisplayLang=en
Considerations for planning a highly scalable and available infrastructure
Information about planning the topology for Microsoft Dynamics AX components
Sample deployment scenarios from a single server to a large, distributed deployment

AX 2009 Installation Guide - http://www.microsoft.com/downloads/details.aspx?familyid=4B681C44-D944-4B3F-B846-1E2A025569FD&displaylang=en
The Installation Guide for Microsoft Dynamics AX 2009 provides step-by-step instructions for installing Microsoft Dynamics AX components. This document also includes instructions for performing initial configuration using the initialization checklist.
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Also it is important to make sure that you meet the system requirements as described here:

*AX 2009 System Requirement - http://www.microsoft.com/dynamics/ax/using/2009systemrequirements.mspx
Microsoft supports the following system recommendations for Microsoft Dynamics AX 2009. Before installing Microsoft Dynamics AX, be sure that the system you are working with meets or exceeds the minimum hardware and software requirements.

Are you aware of any other valuable resources regarding AX 2009 and virtualization?

See below:

Microsoft Hyper-V using Windows 2008 - http://www.microsoft.com/windowsserver2008/en/us/hyperv.aspx
Overview of Hyper-V

Strategies for implementing Hyper-V - http://technet.microsoft.com/en-us/library/bb897507.aspx
Welcome to the Windows Server Virtualization guide

Here is a list of the support virtual platforms for AX 2009
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Windows Server 2008 with Hyper-V
Microsoft Hyper-V Server 2008 Server Virtualization Validation Program (SVVP)

For more information, visit the following Microsoft Web site:
http://www.windowsservercatalog.com/svvp/