This tutorial explains how to attach a data source to a virtual API (virtual service) and insert data into virtual responses.
Below are some help topics that may be interesting for you:
Detailed information on using data sources in virtual responses and scripts.
Provides information on using data sources in ReadyAPI, on various data source types and data generators.
Descriptions of the test steps that you use to work with data in your functional tests.
Describes how to refer to properties in requests and responses.