What is the best way to find tutorials for a given plugin or extension?
Depends on the extension or plugin and where it comes from. Many in the Extension Warehouse and on Sketchucation have tutorials included on the page or in the thread. Others are sometimes covered in You Tube videos and searching there might turn up something useful.Some of the more involved extensions have instructions in PDF files that are either available from their sources or sometimes are included in the downloaded file. One example is Curve Maker. The author’s website has downloadable user manuals for his extensions.