1. Here’s how I created a quick banner using digital elements and the Type tool in Adobe Photoshop or Photoshop Elements.
2. Measure your laptop lid leaving a little space for “bleed.”
3. Create a new document using the width and height you measured.
4. Open a digital background “paper” and copy and paste it into your new document. Resize the background as needed. Adjust the size and position of the background.
5. Using the Shape tool, draw a rounded rectangle.
6. Add your photo.
7. Group your photo with the rounded rectangle.
8. Add a 24 pixel stroke.
9. Apply an inner shadow to the stroke.
10. Type the title.
11.  Rasterize (Simplify) the title.
12. Use the Marquee tool to select and move individual letters.
13. Recolor the individual letters.
14. All done!

Here are a list of companies that have supplies for skins:
Tego Custom Skins (http://www.mytego.com)
GelaSkins (http://www.gelaskins.com)
Schtickers (http://www.schtickers.com)
SkinIt (http://www.skinit.com)