There’s an AWS advent calendar, where new articles will be posted about various aspects of AWS starting Dec 25. If you’re interested in writing or reviewing the articles, feel free to sign up. There are also some great posts from 2016, covering topics such as how to analyze VPC flow logs, cost control, lambda and building AMIs with packer.
There are also articles from years past. I haven’t examined them closely, but I’d be wary of them, simply because the AWS landscape is changing so rapidly, and an article from three or four years ago may or may not be applicable.