The US Tolkien Guide is very similar to TolkienBooks.net. Here is a little bit about what they are achieving.
The U.S. Tolkien archive project aims to compile the complete printing history of Tolkien books in the United States, taking factors into account that are not commonly addressed by other sources, such as cover designs, original RRP (Regular Retail Price) and other data for reprints. Not all of this information will be published in the guide.
Though all the titles published by author J.R.R. Tolkien are listed here, this isn't so much a bibliography as it is a guide to locating the many editions and variants of them.
This guide is very easy to use. For example I clicked on the link to Smith of Wootton Major and was brought to a page very easy to read and find quick information. This page also included some surprises for me as well.
There is also a related works section which must have been quite an undertaking. It includes reference and criticism titles too. There is also a small Links page which bibliophiles may enjoy.
It is uncertain if this site is kept up to date however, there is contact information available.
The US Tolkien Guide