In the 1960's, The Virginia Commission on Constitutional Government published a book called "We the States - an Anthology of Historic Documents and Commentaries thereon, Expounding the State and Federal Relationship". The book is inspired by, and addresses, the idea that the 14th Amendment empowers the US to integrate the schools. The book seems completely unbiased to me. Used copies go cheap on eBay (or Google it).
The Virginia Commission also gathered every congressional debate regarding the reconstruction amendments and condensed them into a huge book with tiny print: "The Reconstruction Amendments' Debates". I consider this book to be extremely biased, because the South is not part of the Congress, and it's all yankees. I don't see how it could be more biased ... State sovereignty is heresy, and secession is treason ... but there is also a contradicting minority view. This book is hard to find, but now and then one pops up on eBay for $20 to $60. One nice thing about it is that it has an index, so you can, for instance, look up "privileges and immunities" and find referenced every time this came up in the debates of the reconstruction amendments.
I have a book called "The Bill of Rights - Original Meaning and Current Understanding", edited by Eugene W. Hickok, Jr. I got mine cheap on eBay. It is the result of several conferences, with many authors. The first conference was in Virginia and regarded the USBOR original intent as a States' Rights document ... I suppose some would call that a Virginia bias, but being Virginian, it seems unbiased to me. The chapter on the Second Amendment is written by Kates and Halbrook, and I consider them to have a bias. But it's a good book, demonstrating how our current understanding of the USBOR is not the original meaning.