You can find translations of a given work in HOLLIS or WorldCat. You can search your author or title (in "" if needed) in Advanced Search, limiting to English.

To find English translations by subject, do keyword searches in HOLLIS or WorldCat, e.g.,

Subject: Cuba description travel
Keyword: translat*
--limited to English.

Index Translationum (1979- ) is a worldwide list of translated books.

A particular source may be included in a collection of primary sources and not individually named in the HOLLIS/WorldCat record.  For example:

Latin American independence: an anthology of sources, edited and translated by Sarah C. Chambers and John Charles Chasteen. Indianapolis: Hackett Pub. Co., 2010, 248 p.
Self-determination, National -- Latin America -- History -- 19th century -- Sources.
Latin America -- History -- Wars of Independence, 1806-1830 -- Sources.

Search for these by searching with Subject terms for your topic plus the term Sources in a Subject search in HOLLIS Advanced Search.