DVI is the same wires and signals for video as HDMI. It just does not have the audio wires and it uses a different connector.
You will need to either run 2 audio cables to the TV to go along with the DVI connection or run optical out from the BluRay to a AV Receiver.
You can buy DVI->HDMI cables from www.bluejeanscables.com. You can just buy an HDMI cable and buy an adapter but the adapter is $25 and a full cable is something like $35.