The Results of the Immediate Process of Production or "Resultate" as known by the Marx connoisseurs is an unfinished manuscript chapter of Vol. 1 of Capital included in the translation as an appendix. I don't think it's ever been published separately in English.

This chapter says not too much that isn't already treated in other parts of Volume 1, except for diverging into some circulation induced considerations probably covered in Volume 2. Most interesting are the sections which discuss alienation of labor, this being a more philosophical side of Marx which is usually not given as much time as the scientific/economic side. It mostly considers the different stages (formal and real) of the subsumption of labor under capital, i.e. the historical process by which the capitalist relations (as opposed usually to the feudal) come to dominate the process of production, and how these stages are characterized by different methods of extracting surplus value. It is apparently unfinished and breaks off into fragments. Honestly worth reading as an introduction to Marx or a summary of the ideas of Volume 1. It's much shorter (around 80 pages) and treats almost every major aspect of 1 without sacrificing detail or dumbing-down or omitting subtle connections.