It is important to understand what the difference between landlord and homeowners insurance is. The department of insurance is very specific in defining the difference between these two types of policies. Homeowners, is if the owner occupies the home. Landlord policy only covers the building, not the land it sits on or the contents of your tenants. That is why you should recommend renters insurance to your tenants.
If you are primarily living in your home and rent out the basement or a room, you need to contact your insurance agent to see how this may or may not be covered under your current policy. If you are planning on using your home as a rental property and moving somewhere else to live, yes you can get landlord insurance for the building. If you are living there however and renting something out to another, it is not typically covered under your homeowners policy.
The other thing to be aware of is, in the event of a loss, if you have a tenant at your residence and did not notify your insurance agent, you may be denied coverage.