I assume you mean Mexican chorizo rather than Spanish, since you specified fresh.
It's easily obtainable in Fells Point and Upper Fells Point. I've gotten at a place called La Guadalupana at Wolfe and Eastern, but it's been a number of years and I think the name of the place may have changed.
SFW in Annapolis also a variety of different styles of fresh chorizo, labeled by country. They seem to cater to a growing Latino population so I'm guessing the three SFW's in Baltimore also carry chorizo.