Office.com offers excellent invoice templates for Microsoft Word that you can complete digitally or print out. Additionally, TidyForm.com has a selection of invoices designed for different situations that you can download as Word documents, Excel spreadsheets or PDFs.
Many accounting programs, such as QuickBooks, enable you to create and print your own invoices. These can often be a highly effective way to manage your invoices because they connect into your accounting systems. As such, you can keep all of your records together and organized. With any such business solution, the key to success is staying on top of maintaining your records.