If your friends are staying at a Disney resort, they can use the free Magical Express shuttle service.
If they are staying off-site and jsut need a ride from teh airport to any hotel in teh area, there are two options:
Option 1 is a shuttle service called Mears. Mears is located at the airport, does not require a reservation, and costs $29 per person for a round-trip bus ride to any Disney or near-Disney hotel. Mears will take a while, however, because the busses typically stop at 3, 4, or even 5 resorts, so it could take as much at 90 minutes to get from the airport to your hotel.
Option 2 is to book a towncar service. There are a number of these services operating at MCO (Quicksilver, Tiffany Towncar, Happy Limo, Atlantis, and a few others I can;t recall offhand). A towncar typically costs $80-$100 per car for up to 4 people, round-trip. Towncar service is like a customized taxi; the driver will be waiting for you at baggage claim with a sign with your name on it, hw will help you with your luggage, and drive you and only you directly to your hotel with no other stops. Included free with the service is a grocery stop (15-30 minutes depending on company) at a store of your choice to stock up on snacks or drinks.
There are
Alamo rental counters at the Disney Car Care Center in teh Magic Kingdom area and at the Dolphin hotel in the Epcot area.