FREE BOOKS ONLINE, many of which are directly or indirectly relevant for ancient Judaism:
First, an excellent website by Mischa Hooker at Loyola University, Chicago: BIBLE, JUDAISM, CHRISTIANITY via Google Book Search. Most of the books are quite old, but some remain very useful. And there are some (generally, I think, incomplete) recent books listed as well, including my 2005 monograph, The Provenance of the Pseudepigrapha. HT the Agade list.
Second, Egyptology Books and Articles in PDF online. Included are quite a few of the older Oxyrhynchus papyri volumes, some other papyri resources, and some Coptic texts. HT Paula Tutty on Facebook.