The easiest way to find scores in our library is to begin with OneSearch. Click on the 'Scores' icon, enter keywords, then click on 'Stetson' and the 'search' symbol. The examples are for piano, but use 'organ' or 'harpischord' for those topics.
Note that the first example links to a digital score from the database Music Online: Classical Scores Library.
Note that clicking on one of the Subject links will expand your search. In this case, to select 'Sonatas (Piano) Scores' will include many other composers' works.
Check here to find information on keyboard studies, chiefly piano. The terms 'harpsichord' or 'organ' can be substituted for the word 'piano' in any of the search instructions.