Google uses the font catull to make its logos and stuff. The font is on sale at Myfonts.com for a wooping $99. But here is a neat tutorial which will enable you to make your own google fonts in three steps using the Photoshop.

1. Start a new document by pressing CTRL + N make it any size you want. Than select the Text tool and choose Book Antiqua as the font, set it for an approriate size that fits inside your document.
2. Select each letter and use the following colors: G – #3364C3, o – #F31903, o – #F7D727, g – #3364C3, l – #44C406, e – #F31903.
3. Once you’ve changed all the colors, right click on the text layer and select blending options..
4. Once the layer style dialog pops up click Drop Shadow and use these settings: Opacity – 46%, Distance – 2px, Size – 3px. Leave everything else as is.
5. At the same layer style dialog click Bevel and Emboss and use these settings: Depth – 166%, Soften – 5px, Angle – 120. Leave everything else as is.

Google Fonts using Photoshop (Via)