Where to start Sales Report/ Dash Board?

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C#

SQL-Server

SQL-Server-2008

, +

Hi Guys I have a system of Online ordering and the process of buying on the store is complete.

My problem now is How can I make a report?
a sales, top customer, top buyer something like that.
and also a report that can generate according to the choice of the user in the calendar ?

can you give a link where can I have a Good start?

Thanks in Advanz :)