1. Create new file with 72 PPI and white background. Create a new Layer. Name it as "Base".
2. Select Ellipse Marquee tool. Drag it on the file. Fill the selection on the new layer with black.
3. Open the desired texture file. Select Move tool. Drag the image on the button file and adjust so that black ellipse will get properly covered with texture. In the layer palette you will get texture layer. Keep this layer selected.
4. Layer > Group
with Previous (ctrl+G)
5. Merge the texture layer with the base layer. For this, select texture
layer. Go to fly out menu of layer palette and click "Merge Down".
6. Layer > Layer
Style > Bevel & Emboss + Drop Shadow
7. You can try out different types of textures as well as base shapes to create different effects.
8. Trim the button to remove unwanted space with Image > Trim
