You can now configure your own lead sources for contacts in the OMS. Users will be able to pick the configured lead source types from a dropdown on contacts as shown below:
To configure your own set of lead source types, simply go to Setup / Sales Settings / Lead Sources and follow the instructions (as office administrator). You can even create sub categories as indicated below:
For groups of offices, a setting is available to configure lead source types for all your offices (enabled by default). Please click on the help & example link on the lead source page.