If you are flexible on the exact book but committed to learning Hindi from a South Indian language base, these resources are equally good, if not better, and many offer free or legal PDF samples.
To understand why the Amrutha Spoken Hindi Book PDF is so heavily searched, compare it to competitors:
While originally a physical paperback, digital versions and related study materials are often sought by students. Paperback: You can find the physical book on major retailers like Amazon India PDF Access:
After conducting a search, I found that there are various sources that claim to offer the Amrutha Spoken Hindi Book in PDF format. However, I would like to caution you about a few things: