Good Book on devadasi (Puranic)
A very good Puranic literature references from Tamil Saivism. Ms. Anjukam (1911) did a great job of research and compiling the book on this topic. She gave a balanced view of both good and bad Devadasi and also their moral codes and lifestyles.
One should read this book to understand the Puranic origins of devadasi in South India and Sri Lanka
Several books on devadasi by Modern scholars have give good details on the lifestyle and suffering of devadasi folks in recent times (30 years ago). This book will help them understand where it all started and gives a perception how things distorted in practice and time.
London Swaminathan gave a good summary on Natyasastra and music origin in pre vedic times till today. In certain astral heavens, dance and music are the way of living and enjoyment along with other exalted ways of pleasure. The similar influences of these astral entries on earth can be seen in the pre vedic/vedic literatures and influences.
A good book overall, a small 112 pages but delivers original research on this hardly touched topic, modern scholars should read this for a wider understanding on this topic, especially coming from Sri Lankan devadasi rather than rapidly evolving mainland India, gives a rare insight.