I have seen lots of people searching for free Vedic astrology books. I have found one website where they have given all ancient Vedic astrology treatise like Brihat Jatak, Brihat Parashara Hora Shastra (BPHS), Saravali, Garga Hora, and Horasara etc. Other than that you will find all four Vedas i.e. Riga veda, Sama veda, Yajur veda, and Atharva veda and upnishadas.
For ease of download I am also giving the direct link of the books here -
Brihat Jataka (zip.74KB)
Brihat Parashara Hora Shastra (zip.195KB)
Kalyana Varma's Saravali (zip.164KB)
Garga Hora by Sage Gargacarya (zip.56KB)
Horasara of Prithuyasas (zip.95KB)
First three books are called Brihattrayi (three biggies) of Vedic astrology. It means that these are the three most important Vedic astrology reads. Without these one can not complete his/her jyotish learning. I hope you will find it useful.
Here is the actual link of the page.
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