In addition to the lists of e-books, all published before 1925 so as to avoid any copyright infringements, there are some printed books to get if you want to at least pretend to know anything about the religious and literary environment in which Christianity was born and grew. So, find and purchase, copies of the following:
James H Charlesworth's Old Testament Pseudepigrapha. Two volumes (vol. 1 1983, vol 2 1985), paperback. The title is a misnomer, as this volume is not restricted to "Old Testament" Pseudepigrapha" as R H Charles' 2 volume Aprocrypha and Pseudepigrapha of the Old Testament (1910) was, but is a collection of fresh English translations of Jewish books and fragments of books composed between 300 BCE and 300 CE (roughly, as some like "3rd Enoch" - a Jewish heckhaloth book dedicated to merkabah/throne mysticism - are possibly 7th century CE or later), with critical commentaries. The material also includes full texts of works like Sibylline Oracles where Christians have re-edited Jewish works. These two volumes are real eye openers, especially the critical comments.
v. 1. Apocalyptic literature and testaments
v. 2. Expansions of the "Old Testament" and legends, wisdom and philosophical literature, prayers, psalms, and odes, fragments of lost Judeo-Hellenistic works
Amazon still has the two volume set available, new, for $46.59 US! Get it!!!
By far one of the most important set of volumes in my library is Emil Schürer's History of the Jewish People in the Age of Jesus Christ (175 B.C. - A.D. 135), Revised edition, T & T Clark, Edinburgh, 1973-1987. This translation was based on the three volume 3rd German edition, entitled Geschichte des Jüdischen Volkes im zeitalter Jesu Christi. The third edition was published as follows: 2nd & 3rd vol. 1898; 1st vol .1901. A subsequent "4th" German edition, identical to the 3rd, was published in 1909; an Index to the whole was published in 1911).
Volume I (ISBN 0 567 02242 0): A New English Edition, revised and edited by Geza Vermes & Fergus Millar, Literary Editor Pamela Vermes, Organizing Editor Matthew Black, 1973, Jewish History.
Volume II (ISBN 0 567 02243 9): A New English Edition, revised and edited by Geza Vermes, Fergus Millar, Matthew Black, Literary Editor Pamela Vermes, Organizing Editor Matthew Black, 1979, Jewish Culture, Political & Social Institutions, Messianism.
Volume III.1 (ISBN 0 567 02244 7): A New English Edition, revised and edited by Geza Vermes, Fergus Millar, Martin Goodman, Literary Editor Pamela Vermes, Organizing Editor Matthew Black, 1986, Jewish-Gentile relationships in the Diaspora, Jewish literature in Hebrew, Aramaic & Greek.
Volume III.2 (ISBN 0 567 09373 5): A New English Edition, revised and edited by Geza Vermes, Fergus Millar, Martin Goodman, Literary Editor Pamela Vermes, Organizing Editor Matthew Black, 1987, Jewish literature such as Apocrypha & Pseudepigrapha (including some that may by Christian revisions of originally Jewish works), Philo, and finally a complete index of all volumes.
If one asks "Why spend $ for these when English translations of Schürer's already exist on the web for free?"
The previous English Translation, published in five volumes as A History of the Jewish People in the time of Jesus Christ (1885-1890), was based on the 2 volume 2nd revised German edition, also entitled Geschichte des Jüdischen Volkes im zeitalter Jesu Christi, published between 1885-1890, ISBN 10 for the whole set is 1-56563-049-1, ISBN 13 is 978-1-56563-049-9).
Vol 2 of the 2nd revised German edition was published as the "2nd Division" in three volumes in 1885. Volume 1 of the German 2nd revised edition was published as the "1st Division" in two volumes in 1890. An index to the 5 volume set was published in 1891.
First Division: Political History of Palestine from BC 175 to AD 135.
Vol 1, 1890.
Vol 2, 1890
Second Division: The Internal Condition of Palestine, and the Jewish people, in the Time of Jesus Christ.
Vol 1, 1885
Vol 2, 1885
Vol 3, 1885
Go ahead, be confused. The newer revised edition edited by Vermes et al brings the bibliography and many historical statements up-to-date (1970-1980s) and corrects Schürer in matters of fact where he was clearly wrong. Also, it is based on the 3rd revised edition, not the second revised version, so is more in keeping with Schürer's thinking as it finally fleshed out. However, this is not always expressly stated, so you have to keep an eye out for notes that indicate modern authors for various excurses and sections. However, you cannot beat the review of the period, especially its literature.
Many of the literary works alluded to in Schürer's work(s), but un-translated in the original or revised English editions, are translated in Charlesworth's work noted above. Unfortunately, it has inexplicitly gone out of print, after all that effort, and has never come out in a paperback edition. I found my copies, new, as remainders, but I doubt that will happen anymore, except for stray volumes. You will have to search used book sites for copies, and collect them as you can. Do it!!!