Here are some blogs/wikis/etc. with good red team learning goodies to behold:
Endgame has a great blog series on hunting for threats without investing huge wads of $$$.
Mubix posted a great bundle of slides/talk/files/etc. at the Wild West Hackin' Fest all about open source pentesting/red teaming. Here's a direct Google Drive link to all the goods he's creating. Looks awesome!
Man, a resource like this wiki make me want to do more advanced red team engagements. It has some really thorough explanations, pics, walkthroughs, etc. about building a flexible and resilient red team infrastructure.