It looks like there is a product that can do this ... I found this link today:
http://stackoverflow.com/questions/15774463/how-to-communiccate-between-jd-edwards-enterprise-one-9-0-and-net. Copying and pasting some sample code from this link below.
private bool CallAddressBookBsfn(BusinessDocument businessDocument, Transaction transaction)
{
AddressBookMaster abm = businessDocument.document.input.AddressBook;
// create an instance of the Address Book Master Business function
// note the use of JDE Transactions
AddressBookMasterMBF bsfn = new AddressBookMasterMBF(transaction);
// set parameters - most of this code is auto-generated
bsfn.DpmnAddressBookNumber.InValue = (long)abm.AddressNumber;
bsfn.DpszSearchType.InValue = abm.AddressType;
bsfn.DpszAlphaName.InValue = abm.Name;
bsfn.DpszAddressLine1.InValue = abm.AddressLine1;
bsfn.DpszAddressLine2.InValue = abm.AddressLine2;
bsfn.DpszAddressLine3.InValue = abm.AddressLine3;
bsfn.DpszAddressLine4.InValue = abm.AddressLine4;
bsfn.DpszPostalCode.InValue = abm.ZipCodePostal;
bsfn.DpszCity.InValue = abm.City;
bsfn.DpszState.InValue = abm.State;
bsfn.DpszCountry.InValue = abm.Country;
bsfn.DpcActionCode.InValue = 'A';
bsfn.DpcUpdateMasterFile.InValue = '1';
// execute the business function
if (bsfn.Execute() != BusinessFunctionResult.Success)
{
// get errors
return false;
}
// assign output
businessDocument.document.output.AddressNumber = bsfn.DpmnAddressBookNumber.OutValue;
businessDocument.document.output.AddressNumberSpecified = true;
return true;
}