How to find Stored Procedures execution time in SQL Server?

You can use Sql Server Profiler for this purposes it provides a lot of useful info along the each executed query and Stored procedure as well.

MSDN: SQL Profiler Data Columns

SQL Profiler displays the execution time for each event

An other straightforward way:

1. DECLARE 2 datetime variables: start/end
2. SET start = GETDATE()
3. EXEC SP_NAME
4. SET end = GETDATE()
5. Execution time - difference between end and start

Assuming management studio or some other environment with an output pane you can;

SET STATISTICS TIME ON
EXEC SP1
EXEC SP2
...
SET STATISTICS TIME OFF