Here are two great websites for building and finding (even more complex) chords:
Build any chord:
You know the name of the chord, you just don't know how to put it together.
Go to this website and it will help you visualize the chord:
Identify any chord:
You have a chord, you see all the notes, but you don't know how to call it.
This website has a nice "Chord ID" function:
Find your scale
PML Course about harmony and chord progressions: