Common problem unfortunately - it's the piss poor crimping design of the joints to the lines that causes the leaks.
As said above, easier to inspect from the bottom where you can see where everything goes - take the bottom splash guard off - if you have strong hands you can even undo the reservoir cap from underneath and check the level - it'll be noisey if running low - or there's a filter under the reservoir that could be blocked - check that also.
If the pump and reservoir seem fine, then the next possible culprit would be the steering rack - squeez the steering rack end rubber boot on both sides and see if you can feel fluid inside (if the power steering fluid is low and the lines aren't leaking, then it's gotta go somewhere, and likelihood is it'll be in the rack boot) - if you have to, slip the boot off just to be sure.
Let me know if you need help on this one - have had to go through this exercise with mine only to realise that it was the bloody swaybar bushes causing a havac!!
