This looks to be a treasure trove of American musical history. If you're not familiar with the artists of the late 19th/early 20th centuries, like me, you can simply browse.
If you would prefer a little context and packaging for your foray into this stuff, I highly recommend Archeophone Records. A carefully executed labor of love. I've ordered a few things from them in the past (the Bert Williams stuff is great) and all have been top-notch.
