From last few months Windows 8 has been a hot topic of discussion and there have been many leaks and speculations about it. Although its beta may not be officially available for couple of more months or so, if you want to have a taste of what Windows 8 “might” be, you can try this Windows 8 Transformation pack!
8 Skin Pack is the latest Windows 8 Transformation pack designed and developed by a DeviantArt member hameddanger, and will attempt to give you the feel and look of Windows 8, according to the features leaked and speculated so far.
To use this Windows 8 Transformation pack, download the zip folder available on homepage at hameddanger.deviantart.com. It will have all the installation and troubleshooting related documents to help you out from any issues, if occur. Please follow the instructions carefully.
We strongly recommend that you create a system restore point first, before trying out this pack, so that you can always revert changes made, should they not be to your liking. If you feel, you can always run System File Checker to replace back the original system files.
Also check out this complete tutorial to customize Windows 7 UI to make it look like Windows 8 UI.
These links may also help you:
Windows 7 Themes Installer
Windows 7 Start Button Changer.