Quoting from [shah]:
There has been seen that many buyers not responding when you sent a quotation to them. Please a system may please be introduce to verify these buyers and suppliers through their country's chamber of commerce and industries.
Get into the real world matey! Why do so many international suppliers whinge about buyers not contacting them back? In the Uk, it is normal practice if:
Your price is too high
you have not replied with EXACTLY what the buyer requires ( Chinese suppliers are famous for this)
You cannot deliver on time
whatever, whatever........ get on with it. You don't win them all