Ok, first off, this tutorial will teach you how to make cool looking text similar to this:

So, to start off, pick a nice font and 2 colors that will be used on your text. They need to be look good together because we will be using them multiple times.
Next, type out whatever text you want to be seen in your piece of art, I chose '3-D'.

Now, rasterize the layer by using Layer>Rasterize>Text.
Now, load the selection by holding CTRL and clicking on the little picture next to the layer in your layers menu.

Take out your gradient tool and choose 'Foreground to Background' and 'Reflected Gradient.
Next, find the middle of your text, and whilst holding SHIFT pull it down straight to the bottom from the middle. Name this layer 'Face'.

Now, if you were doing this on your own, you would choose which direction the 3-D part of the text will be pointing to. In this tutorial I will be using to the right-down.
So, hold CTRL+ALT then hit the DOWN ARROW on your keyboard ONCE, then the RIGHT ARROW, then the UP ARROW. This is the 'rim' layer. It makes the text seem more 3-D.

Now, make the first layer invisible, and using CTRL+SHIFT+E, put the 3 new copies into one layer. Name this layer 'Rim'. Now, go to Blending Options>Color Overlay and choose the brightest of the two colors you chose.

Next, we will make the actual sides of the text. Select the 'Rim' layer and whilst holding CTRL+ALT, hit the DOWN and RIGHT arrow alternatively, until you get the wanted thickness in your text. Make 'Rim' and 'Face' invisible, and using CTRL+SHIFT+E, put all the new copies into one layer. Now, go to Blending Options>Color Overlay choose the darkest color you used. Name this layer 'Thickness'.

Reorder and make the rest of the layers visible so that it goes in the order Face, Rim,
Thickness.
And now to finish it off, go to the first layer and go to Blending Options> Drop Shadow. Now use 120 degrees and whatever opacity looks best. (Degrees would change depending on the direction of the Rim + Thickness of your text if you used your own directions) This adds a shaded effect to the Thickness to make it seem more 3-D.
Before:

After:

Do the same for the Thickness layer if you'd like the 3-D text to have a drop shadow, too.