The Resources page was unfortunately lost with the move to handmade.network, and was never reinstated. However I have found an archive of it, and have reproduced the page below (with links fixed where appropriate). Bear in mind most of this information dates from circa 2014.
I'll ask Casey if he'd like this info posted somewhere more prominent on HMH's project page, or if it would be better suited on handmadehero.org nowadays.
This section is a compendium of links to articles and source code designed to help you follow Handmade Hero on other operating systems or using other editing environments, and for general coding resources related to Handmade Hero.