water lines don't have gaskets, just don't loose the brass washers when you pull the old turbo off. oil feed doesn't need a gasket, it has brass washers aswell but the oil drain does need one. when i did mine i just used some gasket card from work. should be able to get some of this from an engineering supply shop, eg BSC.
as for the steel compression gaskets you should be able to get them from a few places, i've got them from autobahn before. some exhaust shops may have them as will most turbo/performance shops.