So I fell off a huge cliff and died. I was spawned forever and a decade away from my stuff and didn't make it back in time. My map to the world was on me and so it was also lost! Can I find another one somewhere or can I build a new one?
To craft a map from scratch, you need nine sugar cane (every three pieces of sugar cane makes three sheets of paper), four iron ore, fuel to smelt that ore, a piece of Redstone (requires an iron pickaxe or better) and access to a crafting table and furnace.
You can also zoom out the map by adding 8 more pieces of paper and the map itself in a crafting table.
You can also clone the map by adding another empty map with the map you want to clone in the crafting table.
How you cheat your map back to life (Java edition):
(Definitely works on windows and probably mac as well, not familiar with console editions of Minecraft)
In your Minecraft world, create a new map and right click to open it, then save and quit to title.
Open your .minecraft folder. On a PC, you can locate it by typing "%appdata%" in the cortana search bar. Further tutorials can be found here https://minecraft.gamepedia.com/.minecraft
Locate the map you have lost. If you are unsure about the number on your map, you can open maps with Notepad on windows or textedit on a mac. The actual contents are illegible, but you should be able to guess by the length as to which map has the most data.
Ye olde Switcheroo. Rename the file of the new map to the name of the old map and the file of the old map to the name of the file of the new map. Your computer probably won't let you give the same name to two files, so come up with something in between such as "Map_4_a" and then delete the ending after you've renamed the other one.
Log back in to Minecraft. The new map you created should have all the data of the old map. Well done.