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WordPress has a template system, which includes widgets that can be rearranged without editing PHP or HTML code, as well as themes that can be installed and switched between. The PHP and HTML code in themes can also be edited for more advanced customizations. Here we are going to share 13 wordpress themes design tutorials using photoshop enjoy it.
A Photoshop Tutorial that will teach you how to create a Mockup Layout.
learning how to make a nice, clean, eye catching web layout that anyone could make. Really, it’s quite easy
In this tutorial you will learn how to make a very sleek and stylish blue WordPress style bloging layout.
how to create another premium wordpress layout with a special area where you can feature your e-book or your digital downloads.
In this tutorial you will learn how to create a brown ‘Chocolate’ WordPress style layout that is very professional.
create a creative wordpress theme in Photoshop. The layout can be done in less than an hour if you have the right tools on hand.
create a nature inspired WordPress layout
In this tutorial you will learn how to create a corporate wordpress styled layout.

Thank you for listing these great Photoshop tutorials, but I’m wondering where can I go after creating the mockups of the website, in other words, how to convert of migrate my design into WordPress template?
You can search for “psd to wordpress theme tutorial” ,you can see this resources:
http://net.tutsplus.com/tutorials/site-builds/from-psd-to-html-building-a-set-of-website-designs-step-by-step/
http://themetation.com/2008/07/14/how-to-create-wordpress-themes-from-scratch-part-1/
http://hv-designs.co.uk/2009/03/25/psd-to-css-to-wordpress-pt1/