If you don’t have TechNet or MSDN and would like a 90 day trial of Windows 8 Enterprise then Microsoft has what you need.
The Windows 8 Enterprise 90-day evaluation is available to developers to build and test Windows 8 apps on the final version of Windows 8. After installing Windows 8, go to the Windows Dev Center developer downloads page to install Visual Studio 2012 and related tools to build Windows 8 apps.
This evaluation provides a 90-day trial of Windows 8 Enterprise edition. Both 32-bit and 64-bit versions are available as ISO images in the following languages: Chinese (Simplified), Chinese (Traditional), English, English (UK), French, German, Italian, Japanese, Korean, Portuguese (Brazil), and Spanish. In order to use this evaluation, you must register and the product must be activated online with Microsoft-hosted activation and validation services. Microsoft does not provide technical support for this software.
Note that you CANNOT upgrade this evaluation to a full version of the product.