eXtremepixels
Offers phpBB skins/styles with fixed and full width versions. Demo board available for preview.
Jakob Persson
A freelance web designer and creator of several themes/templates for phpBB. Site offers downloads as well as resources for theme and web designers.
Olate - Scripts
Includes downloads, license, and support of free and commercial templates.
PhpBB Skin World
Offers template downloads, tutorial, and FAQ.
Template Magic
Offers graphics tutorials and demonstration and downloads of icon sets and templates.
Template Styles Demo
Offers demonstrations, downloads, and support for templates by Matt Sims.
Vereor Studios
Offers free templates based on movies and commercial templates.