Look at the sites of the major segmental retaining wall licensors (Allan Block, Anchor Wall Systems, Keystone and Versalok). These sites have excellent ideas and information on installation. No concrete footings are required or permitted, so that makes things easier. All the different products work the same way and just have some different appearances.
Most every part of the U.S. and many foreign countries will have several different systems. the use of these is much more common than poured walls and you can go from 1' high up to 45' high.
Most manufacturers also make pavers in similar colors and shades.