Created Partition on Hard Drive but now cannot access rest of HDD

Hello all, I have a WD 750GB GB 2.5-INCH 5400 RPM SATA II HDD that I recently installed on my computer. When I attempted to do a clean install of windows, the windows setup could not find any drives. I formatted the HDD and created a primary partition. I admit I was rushing, and I clicked the partition (80GB) to install windows on. I now only have 60GB of free space on my HDD, but what has...