Thanks for all the suggestions. My studio is insulated and DOES have a lot of metal equipment in it (welders, tools, etc), so the moisture problem of propane will need to be looked into.
I don't have a lot of floorspace for a pellet stove, although that sounds like a way to go, especially if I combine it with some ceiling fans getting the heat down my way.
Do those Propane infrared tube heaters put much moisture into the air? I could see placing one above my 1" thick steel work table and using the table as a radiator, keeping the heat around where I work.
Thanks for all the input so far!
james, Seattle (actually, port orchard and rummages around Navy City all the time)