The only thing I've found which seems to be approaching a magic bullet for EQ is Adobe Audition in "spectral display" mode...download the demo, then open some techno file in it.

There's an icon which lets you switch to the spectral display. You can then "look around" the EQ of your waveform (blotches of colour along a timeline), and see where the bass and kick are doing their thing, how much space the snare takes up, and so on. Things that are clashing will look a bit inverted where they overlap - that'd be phase cancellation or something similar, I think.

If you need to do actual EQ, you can either pinpoint the hz visually which you'll need to boost or cut, and so set your realtime EQ for those freqs (as opposed to flailing wildly around at random with freq and Q on a parametric, which is the usual approach I think), or if you can afford to do it offline, simply select that bit with the marquee tool and choose the "Amplify/Fade" effect, then give it a fair bit of db cut or boost.

That's in my limited knowledge, though; perhaps there are better options about - if you know of them, please share.