The Internet is full of free downloadable goodies for creative artists. Anyone teaching themselves how to design should be able to find plenty of resources online.
This design gallery includes 25 free downloadable PSD mockups. You can grab any of these samples to work with for your own projects. Or if you need a PSD to practice your own design ideas, one of these options should be perfect. Many developers also practice converting free PSDs into HTML/CSS website layouts. Take a look over the list below and see if any PSD mockups catch your attention.