I want to send data from my basic html form to a public excel sheet in cloud (for example skydrive). How do i achieve this connectivity between the excel sheet and the html form?
You can use PHPExcel to read an existing Excel file and add new information to it, then save it back to skydrive.
To save the file into the could you should mount the storage as a local folder/drive on your computer. For skydrive: On Windows it looks something like this and for a Unix system you can use SMEStorage.