This post will provide you with the complete detailed method on how to Create a WebADI Integrator and to upload Customers into your Oracle EBS R12 instance through WebADI.
A complete functional solution to uploading customers, no IDs required whatsoever. Just enter all the functional data available to you (that the WebADI demands for uploading customers) and the WebADI will do the rest for you.
The document you will find in the link provided will guide you through the complete one-time setup process, after which you can start uploading customers directly from the excel WebADI sheet.
You can find the documentation in the following link:
You can find more WebADIs in the EBS – Inventory section.