If you're up for buying a book, I have one called Jelly Roll Sampler Quilts by Pam and Nicky Lintott. There are a number of 12 inch blocks but also some great ones that are 16 inches!
Or, piece a Log Cabin the way Eleanor Burns shows in her first Quilt in a Day book. With 2.5" strips I pieced 24 14-inch blocks in most of one day.
Anita