There's a lot of tools in Elements that don't actually show their head above the surface...... Curves was one of them. All Actions have to be written in full Photoshop (there's no way to make them in Elements) but some of the features of full PS actually work in Elements. For a huge range of free Actions you could try
Texas Chicks Blog - they're mainly 'cosmetic' tools but use some hidden Elements features. For the more technical, the Elements+, as mentioned before, is the best bet.
Even then, when you say you'd like to apply several different curves to different parts, the best tool I've seen for that is NIK Color Efex...... a plug in which, like Silver Efex (for B&W), has adjustment control points which can be applied to any areas, and any amount of them can be used. Still cheaper than CS6!
I'm no Lightroom expert, but I believe that has similar tools - not exactly Curves but with the same effect of altering local areas in many ways........ and that's just lowered its price again.
You may get the impression I don't like Photoshop CS....... and you'd be right. I can accept that there are many pirated versions around the world, but at nearly 600 quid a pop, multiplied by the few million that DO pay that price...... well, it's a staggering income! Not far short of 6 Billion! (The USA price at Amazon.com is $539 - the UK is getting ripped off).