If you come across mention of a Japanese text and wonder if (a) it has been translated and (b) where to find it, start with these lists of translations.
To locate Noh plays, you can try a keyword search (if the table of contents has been included in the information) for the specific play. If you get a lot of noise, you could do an advanced search using the title of the play and subject keywords "no plays" or you can look for a collection of noh plays and browse through the actual books.
The books listed below have collections of Noh plays translated into English. The individual plays are listed in the tables of contents in the library catalog, so click on the links given to see the details.