Create Statement of Account from the accounting software is a Mail Merge process. During mail merging, the fixed field such as debtor, address, the amount due, etc. merges into the Statement template. Besides Statement of Account, documents such as reminders and letters also can usually create from accounting software.
MoneyWorks accounting software does have it own form designer to create Statement and letters. You can use the form designer to create a simple relocation of office notice or a letter of demand; it may not be fanciful but good enough to get the message across.
QuickBooks Desktop, on the other hand, integrates with Microsoft Word to create documents. Check the system requirement to ensure the software you have is compatible with each other. You can check with Intuit, Reckon if you are using Reckon Accounts (formerly known as Reckon QuickBooks), or the QuickBooks reseller whom you have bought the software.
Accounting software is not a marketing tool; consider using a CRM (Customer Relationship Management) software, e-Marketing application, or a Contact Manager software like ACT!, etc. to create marketing mailers such as promotional mailer or ‘keep in touch’ kind of letters to prospects and customers.