i have a problem with my powersteering fluid too. i just recently had to fill it up because i almost ran out. on my car it looks like its leaking out right where the hoses connect to the PS fluid reservoir, so some new hoses may be needed

or i just need to re-tighten the hoses.
i dont know much about cars yet but one suggestion is to check the hoses connected to the power steering fluid reservoir and make sure they aren't damaged, and that they aren't loose either. and just follow the hoses from there and check the rest of the power steering setup making sure nothing has gone ary.