Google recently went through a slight overhaul of their instant preview feature, but the Google Cache links mysteriously disappeared. Here's where to find them in the new design.
This has been driving me crazy for weeks, until weblog NirmalTV.com wrote about the change. The cache links have moved into the actual instant preview itself. All you need to do to get a cached version of a page is mouse over the result, hit the little arrow that expands the page preview, and hit the "Cached" link. If you avoided instant previews like I did, you might never have realised this was there. Hit the link to read more.
How to Access Google Cache Link in Google Search [NirmalTV.com]