windows 2003 hard drive is full, how to fix it

My windows 2003 server?s hard drive is 500 GB, divided by three partitions
C= 100,000 GB (Primary Partitions)
D= 200, 000 GB (Logical Drive)
E= 200,000 GB (Logical Drive)

OS install in C drive our main oracle database installed in d drive, my problem is D drive is getting full. Please help me how can I increase the D drive spaces???..?