If you need to download latest workflow client, for EBS, search in metalink for Doc ID # 261028.1.There are different versions, to be downloaded depending on what version of Oracle RDBMS you would be working on. For example if the RDBMS version is 10g or above, then download patch # 4066964 click here.to go there.
If you intend to work on non-EBS Oracle installation, then you can download from OTN - click here to go there.
