I have purchased SoundSets but I didn't see a download link?

SoundSets are downloaded directly within the players. Open the relevant Syrinscape Player (Fantasy, Sci-Fi, or boardgame), log in if needed, and the new SoundSets should now say “INSTALL THIS SOUNDSET”. Click the link and Syrinscape will take care of the rest. You can always enter the soundsets name in the search bar (at the top of the leftmost column) to make finding the new sets easier.