If you've taken Barefoot Basics, but your clients are asking for more, advanced classes are for you!
Anterior/Side-Lying is for using one footed strokes on the anterior body as well as clinical strokes in the side lying position. I just received those this past week from fellow instructor Kina Ueda in Denver. Great stuff!
Deepfeet2-Advanced Ashiatsu (formerly Deepfeet 2 and the Fusion-blend) teaches the therapist how to use their full body weight to really work the client's muscles deeply. I used two footed strokes on most of my male clients. Ideally, your client should weigh at least 70 pounds more than you.