Is there a particular song that you know of that has these kinds of chord progressions? I would learn as many of these types of songs as possible. I would also do a few google searches and see if there are any instructional articles on making these kinds of progressions. I did one already, but it's been hard to find any that are in tab form rather than note form/sheet music. Here's one from KVRaudio.com:

Okay, for "dark" sounds use this scale:

A B C D E F G# A (NOTE: you can transpose this scale wherever you like. I did it this way since it's much easier to understand than trying to explain it in terms of whole steps and half-steps.)

The chords are made from every OTHER note, so ACE, BDF, CEG#, DFA, EG#B, FAC, G#BD.

For "sad" sounds use this scale:

A B C D E F G A (again, transposable, but would you really want me to say whole step, half step, whole step, whole step, etc.?)

The chords are exactly the same as the other form, except the G# is now G.

So ACE, BDF, CEG, DFA, EGB, FAC, GBD.

if you write a progression you really like in one you can lower the G#s and hear the diff. Of course, the real skill in using the minor is selectively interchangeing the forms; a common trick is to NEVER use the G# except in the EG#B or G#BD(F) chords; it avoids the particularly dark sound of the CEG# augmented chord, and makes the melody more natural sounding, while still creating strength and harmonic tension in the V-I motion (V-I means moving from EG#B to ACE, which is much more powerful than EGB to ACE... not that power is everything, but there you go).