The classical channels to recruit service designers
There are the usual ways to find talents that also work for service design:
Out of university: get in touch with a service design program focused on service design and ask them who are the smartest students they have at the moment
SDN groups and website
Linkedin
Specialised recruiting agencies in Service Design
In some countries, and especially in big cities, there are recruiting agencies that are focused on design and innovation talents like service designers. For example, in the UK, there are these agencies that can help both companies find service designers and service designers find jobs:
Specialised recruiters for Service Design
There are a few recruiters who also specialise in Service Design for either recruitment agencies or big organisations. You could chat with such experts to know how to best recruit talents. Here are a few I could find via Linkedin that I don't know personally:
Finding freelance service designers
If you are interested in freelance service designer, either do a quick search in Linkedin or find talents via one of these directories