REST Client consuming restful web services (delphi)

i have a remote webserver with Magento CE 1.7 shopping cart (linux PHP) i have a MySQL db on a local Win XP PC connected to the internet via a local network. i want to add some new tables to the db and populate them from more than one magento instance located on more than one webserver and each magento instance could have multiple shops. Magento has its own rest api already built in. Later i will build a local GUi that can read magento customer and order data from the local MySQL db. i think that i need a REST client that will run on the same windows xp pc as the MySQL db and populate the new tables with magento data. Maybe each 30 minutes. i dont know how you will solve the issue of multi site and multi shop. i need to know which shop each customer record is from and which shop each order is from. i guess the REST client will need some kind of magento connection config gui and local MySQL config gui. i guess we will store the connections in the database. i also want to post the product 'stock qnty' value, order status 'is shipped' values back to magento if they change on the local db. this must post the data to the correct webserver and magento store !