The Acrobat JS API reference document can be downloaded as part of the SDK from here - http://www.adobe.com/devnet/acrobat/sdk/eula.html
or the online version is here - http://livedocs.adobe.com/acrobat_sdk/10/Acrobat10_HTMLHelp/JS_API_AcroJSPreface.87.1.html
To use the 'doc' object from acrobat in LiveCycle Designer change the 'doc' part to 'event.target'
Hope this helps
Thanks for the response. I do already have code for adding the attachments. The users still want to add additional attachments through the built in functionality. This question was just an alternative solution to a problem I resolved in another way. I had code in the preSubmit event that dealt with attachments. preSubmit does not fire when saving a draft in workspace. If there were an event, i would run the code each time a file were attached. I ended up putting code in the form bridge in the function called when Save is clicked.