State wise road transport info & interstate booking services info
* KSRTC – Karnataka
ksrtc.in – State govt site
www.ksrtc.in/AWATAROnline – State govt online reservation
* APSRTC – Andhra Pradesh
apsrtc.gov.in – state govt site
www.apsrtc.in/APSRTCOnline – online reservation
* SETC – Tamil Nadu
http://www.tnstc.in/ – state govt site
https://www.redbus.in/ – online reservation
* MSRTC – Maharastra
www.msrtc.gov.in – state govt site
http://public.msrtcors.com/ticket_booking/index.php – online booking
http://www.msrtconline.in/ – online booking
* DTC – Delhi
dtc.nic.in – state govt site
www.redbus.in/ – online booking
http://www.delhibusbooking.in/ – online booking
* HRTC – Himachal pradesh
hrtc.gov.in – state govt site
http://www.hrtc.gov.in/hrtctickets/ – online booking
* RSRTC – Rajasthan
www.rsrtc.gov.in – state govt site
http://119.226.41.146:8080/Admin/OnlineTicket.aspx – online reservation
* GSRTC – Gujarat
www.gujaratsrtc.com – state govt
http://www.gsrtc.in/GSRTCOnline/ – online reservation
* PEPSU & PUNBUS – Punjab
http://www.pepsurtc.gov.in/ – state govt site
http://www.busindia.com/pepsu.html – online
* UPSRTC – Uttar Pradesh
www.upsrtc.com – state govt site
http://upsrtc.abhibus.com/ – online booking
* JKSRTC – Jammu & Kashmir
jksrtc.nic.in – state govt site
www.indiatransit.com – online booking site
* APSTS – Arunachal pradesh
www.indiatransit.com – online booking
www.onlinebustickets.in – online booking
* ASTC – Assam
www.assamtransport.com – state govt site
www.indiatransit.com – online booking
www.onlinebustickets.in – online booking
* BSTDC – bihar
bstdc.bih.nic.in – state govt
www.indiatransit.com – online booking
www.onlinebustickets.in – online booking
http://bstdc.bih.nic.in/Transport.htm
* Kerala
http://www.keralartc.com/ – State govt site
http://210.212.239.117:8080/KsrtcOnlineR/ – State govt online
reservation
http://www.ktc.co.in/ – online booking
* NST – Nagaland
www.busindia.com/Nagaland.html
nagaland.nic.in/functionaries/…/Transport/TranspNST.htm
* OSRTC – orissa
busindia.com/OSRTCOnline – online booking
* UTC – Uttarnchal
www.busindia.com/Uttaranchal.html
Popular sites for booking online reservations in inter & intra states are:
http://www.makemytrip.com/bus-tickets/
Wiki World Info 