As an above poster mentioned cabs are pretty plentiful on WDW property, however, one word of caution.....if you plan on using a cab on a regular basis...say three or four times during the week...you just might want to check into renting a car for at least part of your stay from the Car Care Center (near Magic Kingdom) or from one of the car rental desks at one of the hotels on Hotel Boulevard (which is right near Downtown Disney). I believe most of the agencies will provide shuttle service for you to pick up your vehicle and also back to your hotel when you drop off. Where are you staying onsite? That also makes a difference in what modes of Disney transportation are available...for instance if you're at any of the Magic Kingdon resorts (Contemporary, Poly, or Grand Floridian)you can monorail or boat to the MK...if you're at Wilderness Lodge you can boat to MK. If you're at an Epcot Resort(Boardwalk or Yacht and Beach Club) you can walk or boat to both Epcot and MGM. Pretty much the moderates and values you need to use bus transportation. So, it really does make a difference where you stay for transportation purposes. Personally, we always rent a car when we visit because you can plan to add at least 45 minutes, usually more, to your travel time using the bus system. This can really take a big chunk out of your vacation, especially since it's your first time visiting. And, if you're staying onsite, parking at all the parks is free anyway.