You do not mention what passport you hold. Either way your travel agent should have arranged everything for you. I would be VERY hesitant to travel anywhere in teh world if I did not know what the visa requirements were for a particular country. On the other hand the airline carrying you to Qatar would ultimately be responsible for you and will not allow you to board if your paperwork is not in order.

Check out the Qatar Government websites if you have the opportunity.

Good Luck.