Hey Adam! Thanks a lot for your kind words! And I totally get where you're coming from - I've always been intimidated by responsive designs as well, but then I learned about percentages and screen-size specific designs and though the process is a little tedious, I was able to finally make my designs responsive and conducive on different screen sizes.
As for resources, I usually refer a lot to CSS Tricks, Codepen.io, W3 Schools, GeeksforGeeks, and good old StackOverflow when I'm building my websites. Hope this helps! Also, feel free to reach out to me via Twitter - I would love to keep in touch with you there!