closed as off topic by Philip Regan Aug 11 '11 at 11:53
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Well I would say try playing with a border and internal drop shadow. In the example you posted each of the buttons has a 1px solid border which is broken with a light drop shadow. Some of the boxes seem to actually be using a type of outer glow instead of box shadow.
Reduce the opacity on that a lot, maybe 10-30% and very light coloring. There is a gradient style you can use as well. But I'm guessing you know about that if you're attempting to construct such a button style!
For more you can see this tutorial :
hope this will help...