How do you get a map in minecraft 1.5.2?
For single player, maps can be extracted to %appdata%/.minecraft/saves.
For multiplayer (provided you're the host of the server), maps should be extracted to your server folder, with 'server.properties' edited in Notepad to reflect the world map's name.
once you download the map (this goes for any downloaded map by-the-way) take the folder with the map files, and place it in the "saves" folder of your minecraft files. to get to the minecraft files on Mac: go to finder library application support Minecraft OR - shortcut is SHIFT+COMMAND+G then type: ~/library/application support/minecraft