Client side HTTP Upload software

I need a client-side Windows software that will allow a user select multiple files on his computer, enter in login information, and the software will automatically upload through an HTTP POST connection that will be given through a website. How this work is, a user logs in through the software. The software will send the login information through an HTTP or HTTPS connection to a central server. The server will respond with the URL for the HTTP POST script and an upload code which your software will submit along with the file. You do not need to provide the server software or code. I will provide you that information as well as a test environment. Project requirements: 1. Source code must be included. If you use any third party libraries, the libraries must be properly licensed for distribution. 2. I would prefer the source code to be in Visual Basic or Visual C#, but if you want to write it in something else, check with me first. 3. Software needs to have a space for my logo, which I will provide at a later time (it is being designed). 4. Software should be graphically attractive and simple to use. 5. Software must allow a user select multiple files from different locations. This means more than just the standard Open... dialog box. User must be able to add and delete files from the transfer queue. 6. During the HTTP POST Upload process, a status bar (% complete) would be nice. 7. You must have experience in writing this sort of software. Please provide past examples if possible. 8. You must stand behind the software and be available to fix any bugs that may arise. If there are modifications to the software that is needed, I will pay you extra for these changes. However, bugs are your responsibility. Thank you!