QuickBooks designed for Mac by Mac Users. Easily create invoices and sales receipts to keep track of who owes you money, what they bought, and when they paid you. With just a few clicks, you can log hours, bill clients, and add reimbursement expenses to your invoices. You can keep track of important dates with iCal/Calendar integration and import Address Book/Contacts into QuickBooks to maintain up-to-date contact information.

http://quickbooks.intuit.com/mac/