Repairing poor soil drainage
 

I've got about a 5000 sq ft back yard which is jsut over a year old.
The property prior to the lawn installation was very rocky and pourous (I
mean VERY). The landscaper then put down about 4 inches of fill dirt and
another 4 inches of "top soil".
Over the course of the winter the yard has turned into what I would call a
marsh. You can actually hear the water trying to drain through the soil but
for the most part it's a muddy mess.

I don't have the bucks or the inclination to tear up and till the entire
yard to try and break up the soil and introduce some courser material. Is
there an efficient (both cost and time) solution that will get me some
better drainage?

Thanks so much.
~Torben