How to inject LAN drivers into WDS Server BOOT images

We use WDS (Windows Deployment Services) to image large numbers of computers. Lately we have been using a Windows Server 2008 R2 WDS server with a Windows 7 boot image. However several times we have found that newer PCs/Laptops (manufactured after Windows 7) have trouble PXE booting in to the Windows 7 boot image, due to the lack of LAN drivers.
We found that these drivers need to be "injected" in to the boot image (a .WIM file) to enable the PC/Laptop to be imaged using WDS. After several attempts we found the following procedure worked quite well to achieve this.
Before You Start

• You’ll need a full install of WAIK (Windows Automated Installation Kit,) as it contains the necessary tools to manage WIM files. This can be done on any system, but if you’re running WDS it is best to perform the injection on the WDS server.

Windows 7 Sysprep and WDS

I decided to try the Sysprep process for windows 7 in advance of our roll-out early next year, to get a feel for the process.
UPDATE: I have added a new Blog Creating a Windows 7 Sysprep unattended XML with a breakdown of the unattended XML creation and configuration.
For the test base image, I want to create an "admin" image with administrative tools, AD, Exchange 2007 and SQL 2005 on 64 BIT Windows, to be used by the sys admins for further testing.

Upon searching, the majority of posts are Vista related, but this step by step guide was found to be very useful, particularly in creating the answer file using the WAIK (Windows Automated Installation Kit), and I would like to take this opportunity to thank Brian Lee jackson.