Many universities with Ethnomusicology departments (Wesleyan, University of Madras) have digital libraries. If you are a student, you can request access to their scanned copy for academic use.
Lalgudi’s Tillanas are famous for their infectious rhythm and melody. They are often set to rare talas (rhythmic cycles). Having the notation allows a student to decode the complex rhythmic korvais (patterns) that might be difficult to catch just by listening. lalgudi creations book pdf