While trying to change the settings of my portable Sumatra (which has proved fruitless up til now - portable, right!), specially that hideous yellow background, I found this three online colour picker sites, better keep them at hand:
ColorPicker.com - Quick Online Color Picker Tool - Quick Online Color Picker Tool - simple, with clear instructions and links to a colour chart
Sphere: Color Theory Visualizer - a bit more complicated, with more options but no clear instrucctions, so probably not for the uninitiated (like me)
Color Scheme Designer 3 - as the name indicates, this one helps generate a whole colour scheme, and has plenty of options; no instruccions, but rather easy to crack.
Obviously, after finding my colour with the first site, I didn't dig deeper into the other two. Also, I was pretty sure I had some similar addresses here, but couldn't find them. I will have to check my search feature.