This is very useful for those residing at chennai (to book tickets online).
Just visit this website to book a ticket.
You need to pay Rs.10 extra with Ur ticket price. If u give all details there, they will give one code. U need to remember that code. U should b there in Koyembedu Bus Stand before 30 minutes from traveling time. At the reservation counter u need to tell ur code number and u need to pay.