Volvo steering fluid leak?

Just as i was praising my newly purchased S80 D5 2005, I felt a lil "PUTH" sound whilst driving at 25mpg and then heard a whiny noisy sound. I pulled over and saw yellow fluid similar to new oil dripping - im guessing this is the steering fluid.. Need help on what are the options - the car did steer on the way home but made a nasty noice when turning.. now its parked up and its dripped out almost - Experts .. whats the damage and repair costs - Cheers