After having it on my “maybe in the future” list for years, I finally gut sucked into playing Infinity and really enjoy it. Here are a couple of online resources that can help you when starting out, but also later on.

• Official Infinity website
• Infinity download page: Includes the rules, army and weapon lists, the current tournament documents (season 9 as of writing of this article), the FAQ, printable markers.
• Infinity Army: The official online army builder. Also available as Android app.
• Infinity Wiki: Full rules reference, including the FAQ entries. A great tool that is actually quicker to search than the rules PDF files.
• Corvus Belli forum: The new official forum. You might have to switch the language to English on the bottom.
• Hacking Helper: Lists all hacking programs by device and target (N3, not updated for N4).
• The Dice Abide: While mostly covering USAriadna and Combined Army, this blog also has a number of articles that cover some of the basic rules and principles of Infinity.
• Infinity on 1d4chan: Basic game and faction overview and tactics articles.