How to get a delta robot to go to a set of coordinates...help please some math genius :P

Hey guys!

It's been snowy weather here so I've been stuck home from school with tons of free time (yaaaay).

I posted here earlier wondering what I should build out of my LEGO Mindstorms kit, and I said I might build an M&M sorter. Well I completely ignored that after I got the (probably stupid) idea to build a delta robot.

I got one working, and I can program basic movements of it (controlling each individual motor with accuracy down to about 3 degrees; the sensor is accurate to 1 degree but the gears have a little bit of play in them...it is LEGO after all)

I want to have a function in the program that will allow a user to put in coordinates (in X, Y, Z format) and have the robot go to them. 

My robot is almost exactly like this as far as design goes.

I've only been through Geometry 1 so far, so I'm pretty much at a loss for calculating this. Can some math genius (looking at you Wendell) please help me, or at least point me in the right direction to figuring this out? Has someone already made a program to do this and I'm just not finding it on Google?

HELP!

Thanks

well, I mean there's this 
http://www.cim.mcgill.ca/~paul/clavdelt.pdf

But, basically it's a lot more math than I'd like to be doing as a hobby