Looking to export product listings from Salesforce and importing into Craft Commerce?
Generally speaking, it looks like you'd need to create a Craft plugin that imported the Salesforce PHP Tookit library/classes.  From there you'd query your Salesforce web endpoint for the data you're looking for.

Once the data gets back, you'd programatically create the products using Commerce's service layer API.  You can see any example of that Commerce uses itself to populate default content on a fresh installation in the Commerce_InstallSeeder class in commerce/Commerce/Seed.