I am currently trying to PM Magento projects and I was wondering if there are any resources that people can recommend in order to get started. Any literature on this would be greatly appreciated.
You need to be an expert in using Magento (especially the Admin) and familiar with most of the default features.
As boring as it is, read the Magento User Manuals (1.9x and 2.x).
Also you should have access to a completely non-customized version of Magento for each major version your development team is working with. (1.8.x, 1.9.x, 2.0.x, 2.1.x, etc). Use this to familiarize yourself with the Magento default features and to compare for task based QA/UAT.