Hi Saeed,
With Release ECC5.00 Support Package 4, PDF-based forms are provided for withholding tax reporting (this is described in note 772491). For year 2014 the pdf format for 1099 report was delivered via note 2095280 - US Legal Change 2014 - 1099 Adobe forms and Smartforms, this note is relevant for ECC5.0 system version. You may start by implementing this note and follow its pre-requisites.
Regarding the adobe forms for 1099s. Currently SAP supports the following print forms layouts:
1099-MISC: Miscellaneous Income
1099-G: Certain Government Payments
1099-INT: Interest Income
1099-K: Payment Card and Third Party Network Transactions
1042-S: Foreign Person's U.S. Source Income Subject to Withholding
Best Regards,
Ester Theodoro