For anyone who is interested, the final volume of the Collected Essays is out in paperback now (hardbound to be released in a few more weeks); it includes all his philosophical and biographical essays (including the humorous ones), along with such things as "Cats and Dogs" and his ponderings on the political scene -- the last might come as a surprise to those who know HPL only through his fiction, yet they helped to form some portions of his fiction (especially the societies of the Old Ones and the Great Race).
And for LMA: They are supposed to be putting out his letters to James Ferdinand Morton sometime this year ... you'd probaby find quite a lot of that very interesting, as Morton was a very progressive thinker, one who fought for equal rights and supported sexual equality; and the debates between them makes for interesting reading, from what I've seen...
And sometime next year they will, apparently, be putting out both sides of the correspondence between HPL and CAS; and that should be of interest to several people around here, as each sparked the other's creativity several times....
Collected Essays 5: Philosophy; Autobiography & Miscellanyby H P Lovecraft- Hippocampus Press