These three sources summarize and evaluate what they consider the major publications from a given year. Coverage generally lags behind several years, meaning the 2018 volume will cover 2015/2016 publications.
Year's Work in Critical and Cultural Theory: Annual set of essays reviewing the year's scholarly publishing in major critical schools and theories.
American Literary Scholarship: Annual set of essays reviewing the published scholarship during that year; covers works on American authors, genres, periods, and themes.
Year's Work in English Studies: Annual set of essays surveying the state of scholarship on literatures in English and English language studies.
Use these directories to identify periodicals (scholarly journals and mainstream magazines) and book publishers by their subject or genre focus.
MLA Directory of Periodicals (part of the MLA International Bibliography--click on "MLA DIrectory" at the top of the search screen to get to the directory): Major directory of periodicals in literature, rhetoric, language studies, film, and drama which includes contact information, subject scope, submission requirements, circulation numbers, and often acceptance rates.
Ulrichsweb: A directory of over 160,000 magazines and journals; use the Advanced Search to limit to scholarly/academic journals. The subject categories are very broad, i.e., "Education" so try a title search if the subject search isn't retrieving what you need. Major titles usually have a yellow star next to them and often link to reviews from Magazines for Libraries or Library Journal.
Literary Market Place (available at Reference Desk): Directory of U.S. trade and university press book publishers with a broad subject index.
Association of American University Presses Directory (Main Ref Z231.5 .U6A7 2013): Detailed directory with a subject grid of publishers' areas of focus.