Digital Resources:
1)
THIS SITE- Some of my best ideas have come from or been critiqued here.
2) Wikipedia- Basic info about anything, great if you're a GM with an eye for detail. If you like to give a specific history context, some countries have pages "(country) in (year)" that can give great real-world context.
3) Invisible Castle- rolls and records dice rolls (alternatively, random.org or wizard's have them as well)
4) The PDFs- it's good to have multiple copies of
Your Story lying around (maybe not
Our World though- personally my players don't have that one so they can't just look up what I'm throwing at them)
5) D&D, other RPGs- find unique creature builds online, then adapt them here.
6) DFRPG wikis- I know of least 2 floating around, with example settings and such-
this one, and the one I'm just starting with info about the various games I've played (I'm sure there are more).