The rail's Reports entry opens Bill details, Vendor credit details, Purchases by vendors, Purchases by items, Payable aging summary and details, Vendor balance summary, Transactions by vendors and Payments made. The Form 1099 reports live under Accounting → Reports. See Chapter 19.
Withholding tax — per vendor and per category for a period: base, withheld, remitted and outstanding, tied to the Withholding Tax Payable balance, with every deduction listed. Remit posts the journal (debit the liability, credit the bank you choose) for the period's deductions and marks them remitted; PDF on a vendor row downloads that vendor's certificate for the fiscal year — every deduction with its base, rate and amount.