One way is if you know the name of the new service that will be created when ordering it via the service_templates, then you can find it via:
The other way is to find the service by service request id, when you order the service via:
You get the service_request back which would have an id.
Assuming the service order is approved and goes through and the service is created, then you can search for that service via the service_request id as follows:
which you can then retire as per http://manageiq.org/docs/reference/latest/api/reference/services#service-retiring-now
Hope this helps,