Well, all of the comics and novels "signed" by Lucas or with his "stamp" are cannon. There are some the predate the known 2 film trilogies and some that continue on in the times that came after it. There are also many stories and many periods covered by stories of games. For example, Star Wars the Force Unleashed 1&2 develop the time between the 3rd and 4th movies and the rise of the empire.
the two cartoon series around the clone wars, both the normal cartoon one from cartoon network and the CGI one that is still airing, develop the period of time during the clone wars that happened between the 2nd and 3rd movies.
Most games also come with novels or graphic novels, making their stories cannon.
a resource that might help you is
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because not only can you se summaries of the stories as you can find the names and novels that described and talk about each part. Its very complete because star wars fan base is very dense and vast as well as dedicated and precise.
