Originally Posted by
AAJetMan
No guarantee, as mentioned by OP. A better bet, but must still beware.
Follow the clearly posted signs .. at least in India, a guy from the prepaid counter usually takes the receipt + copy from the clerk, follows you with your luggage, escorts you to the cab that's allocated to you from the rank. Keep an eye on him .. and feel free to tip him. The clerk will also tell you / the escort guy the license tag number of the cab you've been allocated - and chances are, you'll find that number printed on your receipt.
If that isnt the case - well, follow the signs - at least in some of the newer airports (BOM/DEL etc) they're pretty clearly posted.
And for some of the ranks there's usually a desk somewhere outside the rank with a dispatcher who will take your receipt and point you to a driver.
Some random driver comes up before you ask for the number, and somewhere "out of the blue", like just when you exit the terminal .. feel free to tell him to get lost.