Automate Import of Quickbooks Invoices

I have a web based application that I use to record order transactions. I will export these transactions to a file that will need to be configured for automatic import into Quickbooks Pro 2011 using the Quickbooks SDK. I will have 50 to 100 invoices that will be downloaded every month and I want to automate the process of ingesting them into QB. I would like to use VB6 as the front end for reading in the downloaded invoice data and then writing that data to QB. I want to structure my invoice data in CSV or XML format. (If you have suggestions, I can use that.) I need is the logic that will open the connection to my QB company file, and the data structure and code required to properly populate my invoices. Each invoice will multiple entries (all single rows of data): Item, quantity, description, rate, amount... posted to accounts receivable.