Migrate Oscommece to Magento ecommerce.

I would like to migrate my Oscommerce website to Magento ecommerce website. I am looking for experience Magento experts that invlove the jobs: 1. Install a new version of Magento and modify Magento with some customizations that may need. e.g. add bank account information, shipping information and paypal, etc. 2. Apply my choice of design template to Magento. 3. Export customer data, order data, products listing data, etc from Oscommerce to Magento. 4. Export the same customer logins that they used to have from Oscommerce store. I prefer to develop the Magento store on a test server first and after make sure everything is running the way I want then switchover the Magento store to my current website that running oscommerce.