Thanks for the commenst guys. Geoff, I use a Canon 5D with a couple of lenses – 28-135 for the wide angle shots and 70-200 for the close-ups. The nice thing about the 5D is that it handles high ISO quite well (ie prevents the images from becoming too grainy) which makes it good for concert photography. It’s quite old now though, and I think some of the more modern SLRs are even better in low light.
In terms of post processing, I load everything into Adobe Lightroom, and then play with the different presets until I find one that I think complements the image. Sometimes the image is fine as it is, sometimes it looks better in black and white, or blue toned or sepia (my purely subjective opinion). One particular treatment I like is cold tone, where all the blue and green tones are boosted a little but the reds, oranges and browns are suppressed (reduced almost to black and white). It doesn’t work with every image but occasionally it produces a really nice effect. I might then fine tune the contrast etc until I'm happy with the final result.