sources (background info)
http://theconversation.com/guide-to-the-classics-tacitus-annals-and-its-enduring-portrait-of-monarchical-power-107277
https://theconversation.com/guide-to-the-classics-suetoniuss-the-twelve-caesars-explores-vice-and-virtue-in-ancient-rome-85608
these were recommended by one of my professors just in case we were struggling with the context of two of our major sources for my roman empire class. all the guides to the classics are great!
sources (actual translations of works)
http://www.perseus.tufts.edu/hopper/collection?collection=Perseus:collection:Greco-Roman free translations of many of the major graeco-roman works! great for when you’re desperately trying to find an example the night before an essay is due.
http://penelope.uchicago.edu/Thayer/E/Roman/home.html loads of latin sources and pretty good quality translations.
http://lexicity.com/ if you’re interested in learning basically any ancient language ever this is a great start!
http://blog.journals.cambridge.org/ covers all different spheres of academia but they have an excellent antiquity section.