Open access to The Bookman USA (1895-1933) and The Bookman UK (1891-1934).

Search via Google:

site:http://www.unz.org/Pub/Bookman keyword

Also quite a few pulps from the 1940s and 1950s, including Fantastic Novels and Fantastic Adventures and some later Weird Tales, which have Lovecraft reprints.

You can also search the entire archive via:

site:http://www.unz.org/Pub/ Lovecraft