Addresses are available at https://data.cityofsalem.net/search?q=address
Buildings are definitely in city GIS but not in the public open data site yet. They could probably be made available on that site if someone asked.  The roads are in there too under "centerline". The roads are about to go through a big update.  I don't think road centerlines are very useful as most of this is mapped already, but useful for road names.