As part of my ongoing reading on this subject, I continue to be intrigued about the significance of the
Jeselsohn Stone or Gabriel's Revelation, which messianic scholar Israel Knohl believes refers to the establishment of a Jewish concept of catastrophic messianism.
For those whose interest in historical Jesus studies is based on an interest in history, rather than claims about ancient history based on one arrogant "ancient historian's" depiction of classics and a guy who received a degree in classical languages years ago, there are a number of highly informative sources that do not require the ability to read ancient Greek, Latin, Hebrew, Aramaic, Coptic, etc.
For those with some patience and pocket money, JP Meier has produced four volumes which can be used for the general reader or expert, and is designed to be so (all the technical details are relegated to endnotes, and for topics too broad for endnotes we have excurses). It is also designed to be as objective as possible, and given Meier's actual beliefs contrasted with his findings, I'd say he did a decent job.
For those whose ability to read books outside of their business or academic expertise, there are a number of books that are not, like Ehrman's, designed for those with a knowledge of history a high school education might provide. Of course, an understanding of historical methods and their epistemological bases is pretty fundamental, but there are nonetheless a few books that are intended for the general reader yet do not assume more than a high school education.
A textbook by Gerd Theißen & Annette Merze,
Der historische Jesus: Ein Lehrbuch, has an English translation.
For those who prefer a less academic oriented work for the layperson, we have e.g.:
Van Voorst, R. E. (2000).
Jesus outside the New Testament: An introduction to the ancient evidence. Wm. B. Eerdmans Publishing.
Casey, M. (2010).
Jesus of Nazareth:
An independent historian's account of his life and teaching. Bloomsbury T&T Clark
Dunn, J. D. (1985).
The evidence for Jesus. Westminster John Knox Press.
Eddy, P. R., & Boyd, G. A. (2007).
Jesus Legend, The: A Case for the Historical Reliability of the Synoptic Jesus Tradition. Baker Academic.
Habermas, G. R. (1996).
The Historical Jesus: Ancient Evidence for the Life of Christ. College Press.
as well as various companions and handbooks published by OUP, CUP, Routledge, etc., and for those whose limit on this particular subject isn't Ehrman's quality, there are a significant number of serious volumes which are nonetheless intended for the general reader.
For those who are more interested in reinforcing opinions already held, there's the internet. It's an invaluable tool to provide those who haven't read the technical literature in a field with plenty of ways to explain the state of research without actually reading any of it, and to malign historians and academics they've never heard of via unwarranted accusations biases.