Sharerpoint 2010 Purchase Order System

[kb2014]

I have been tasked with finding some software / templates which can get the purchase order approval online and minimise paper usage in the school, can anybody recommend software or companies that provide web parts or stand alone software that we can integrate into our current SharePoint 2010 set up? We are also using SIMS FMS. Ideally we would like an online purchase order form that departments can complete. The purchase order gets approved and then gets send to Finance. Im assuming this part is a straight forward InfoPath form with approval which I could possible do, but I know they would like to export the orders as an xml file which can then be imported into SIMS FMS. I'm not a coder. I'm looking for an out of the box solution, what is everyone else using?