You have just finished reading David Foster Wallace’s Infinite Jest. You, like me, probably have questions. I present the resources that I have compiled over time.
Infinite Jest on Goodreads. I like to start here after I finish any book. Reviews tend to have a palatable balance of insight and colloquialism.
thehowlingfantods is an oft recommended blog devoted to David Foster Wallace.
Trade Paperbacks’ Words, Words, Words: The Infinite Jest Liveblog commentates the entire tome in bite-sized chunks. Included are appropriate media to back up non-obvious references in Infinite Jest and an opinionated biography that sheds light on the themes.
A Character Guide (The original page 404s, so this is the wayback version). It is what it sounds like.
Aaron Swartz authors a very popular theory explaining the end of Infinite Jest which is worth considering.
Elegant Complexity is a companion guide to Infinite Jest. I have not read it myself, but it is well received by the Goodreads community.
As for related work, I unhesitatingly recommend E unibus pluram: television and U.S. fiction, a critical essay written by Wallace, about entertainment in the post-modern world.
Of course, reddit has interesting material on the matter.
A brief note regarding etiquette — research (online, not by experience) has led me to understand that prattling about Infinite Jest is considered pretentious by some, so tread considerately.