Taxis are easily found on the streets of Kuala Lumpur and are not very expensive either.  It is better to fix the rate of your trip as most taxi drivers will not use the meter. Be sure to bargain though. The yellow premium taxis are slightly more expensive than   the regular red and white ones. There are also surcharges for radio call, baggage, etc.

If you want to pre-book a ride try calling the following cab operators:

Comfort Cabs +60-3-62531313
Sunlight Taxi +60-3-90575757
Public Cab +603 62592020
Uptown Ace +603 92832333