I have made virus with pGIPZ and I need to resuspend the viral pellet. How do I do this?

Actually you cannot see a virus pellet. What you are seeing are the serum proteins that get spun down from the media. There may also be some genomic DNA from disrupted cells, which does not go into solution. Resuspend the "pellet" in DMEM, no serum, by letting it sit for 10 minutes then gently pipetting up and down 20-30 times. Then transfer this into a microfuge tube and spin in a microfuge full speed for 3 minutes to pellet the protein debris. Aliquot the supernatant and store in a -80C freezer.