Max Wawrzyniak wrote a great series of articles for Duckworks Magazine (written for and by those wacky homemade boat builders) on buying, repairing and maintaining old OMC (Evinrude, Johnson, Gale and store brands) outboards.
There isn't one index page that covers ALL the articles, so I've put one here.
The perspective is someone looking for "Cheap Power" for a home built boat, not that of an outboard collector (interested in the engines for their own sake). Purists may take issue with Max's advice, but his writing is easy to read, and Max's articles convinced me that I could work on old outboards, maybe he can convince you too!
A GREAT thing is that the articles include parts diagrams and service bulletins you might otherwise have to hunt down (or might not even know about)! My only complaint is that ALL the multi-part "Start to Finish" examples are on older (and stranger) models than he advises people to buy!
The articles were republished as the book Cheap Outboards, which is organized by engine area (carb, magneto, starter).
(My comments in italics)