Everything you need to build your own Muffsy Clone is available at his site. There's an impressive lot of information about his design goals and on how you should go about building the project.
Go here to see all of it, and build your own Muffsy Clone:
Theslowdiyer - Muffsy Clone Project Files
If you are looking for a suitable power supply, theslowdiyer's got you covered as well with his GP-PSU v2.