Need to generate site URL from database

Hi,
I am asking one question plz tell me
My task is I have  one url like this "http://example.com"
I am passing one parameter alog with url like "http://example.com/Tagid=12345"
I want to display SiteName(ColumnName)in database table value(EX:www.asp.net) correspondind Tagid number
I want to Final Result is
IActual URL is:"http://example.com/Tagid=12345"
I want to display::"http://example.com/?Tagid=12345\www.asp.net"
"www.asp.net" This value comming from DATABASE TABLE
Table Information
Tagid            SiteName
12345       ...