It is hard to get rid of bed bugs as compared to cockroaches etc. The regular spray in the market is also not so effective. They hide during day time at various places and come out at night. Generally pest control companies give the treatment two times with an interval of 15 days. This ensures that new bugs coming out of eggs are also killed.
You can contact PCI India ( http://pcilindia.com/home.asp
) or Godrej HiCare ( http://www.godrejhicare.com/
). These two companies are well known in pest control space.