GitHub has all the things, seriously, it rules. OKFN hosts open data there. So do I. As do most Code for America brigades. But you can also get a free datahub.io account, at least for an organization and you can upload there.
You should also check out your area. Here in Virginia, there is an OpenVA data portal, and anyone can upload related data after signing up. Google your area and see if there are any municipal portals you can hit up.