If you need a specific title or author (e.g., Sri Potuluri Veerabrahmendra’s Kalagnanam or Jataka Tattva by Sri Kovidakanta Rao ), reply with the name, and I can help trace a legitimate PDF source.
Old Telugu astrology books are often out of print. Here is a tiered search strategy: Old Astrology Books In Telugu Pdf
Several foundational astrological treatises are available as digital PDFs from archives and specialized repositories. Brihat Jataka If you need a specific title or author (e