There are a few options, but using a SP may not be the best for you. Take a look at this article: http://support.microsoft.com/kb/321686. If the Excel file is always the same one and it needs to be updated, it may be best to set up a dataconnection in Excel where the data flows back and forth dynamically. If it's only going one way (to MSSQL) but the file is always the same and it needs to be triggered from the SQL Server, a linked server or distributed query might work well. If you need to sync with several Excel files, give SSIS a look.

Hope this helps!

Chad