Waypoint System with Taxi Feature - Works similar to TomTom, clicking the Quest POI in your Objective Tracker will automatically place a waypoint for the quest. The waypoint arrow will turn green if you enter the selected quest area. You can also create your waypoint by CTRL + Right Click on your map and you can also link them together by holding SHIFT + Right Click on your map.
The World of Warcraft API has a list of functions that you can interact with and to talk with WoW using Lua. These are your building blocks for manipulating WoW windows and chat boxes and so forth. Looking at these for the first time can be very daunting. But don't be discouraged. After getting more familiar with Lua the WoW API gets much easier, and the documentation gets much easier to read. Keep in mind there are many different ways to accomplish your goals, so when going though the API keep looking until you find a way that best suits what you need.