Look, if you have the funds to be in a limo, tip the guy
If you don't like that, take a taxi, because you probably don't belong in a limo/black car anyway.

If the car is paid for by the company, tip the driver, don't be a cheap skate!
If you order the car yourself, tip is usually included.

I found in my experience, tipping the driver up front (meaning right when you get in) you will receive MUCH better service!!!! If you use a limo service regularly, by all means TIP!!! Remember, the guy in front CAN make you miss your flight, or meeting!!! Just remember, like in a restaurant, if you don't tip your waitress, and you go there often, your food is going to take awhile to get to you!!!

Short distance $10, medium distance $20. Long distance varies from $40 to $100.

Like I said if you complain about such a small amount, then you probably don't belong in a limo/black car.