View Existing Table-valued Parameters I have seen many tutorials on how to create a table-valued parameter - but how do you view a table-valued parameter after it has been created?  

I would prefer a way of using the GUI in SSMS but T-SQL would suffice as well.
Please use this code to create a table value Parameter.

--create a new database
USE [master]
GO
CREATE DATABASE DemoTVP
GO


--Change context to the new databse
USE [DemoTVP]
GO

--creating table-Valued Parameters
CREATE TYPE LocationTableType AS TABLE   
( LocationName VARCHAR(50)  
, CostRate INT );  
GO  


Then you see the above created table value parameter in SSMS. 



Using TSQL you can see the same.

USE [DemoTVP]
GO
SELECT * FROM [sys].[objects]
WHERE [type] ='TT'
ORDER BY create_date DESC