new to sharepoint - import xml data (& keeping it up to date)

[duejay]

everytime a user submits my webform an asp.net file updates an xml file with the new form data. This data must be accesible in sharepoint.

1 - how can i import this xml file (what ere the rulez? i saw an option and was able to import an excel spreadsheet)

2 - the data in sharepoit has to be up to date everytime a user wants to see what new data was submit via the form.
When i imported the spreadsheet, and the original excel spreadsheet was edited, this file had to be imported again in sharepoint to be up to date.