LuaPill

LuaPill (short for "Practical Isometric Layering Library for Lua") is an engine for generating isometric maps for Löve2D and Lua.

function love.load()
   map = require "luapill"
   local config = {
      tilewidth = 128,
      tileheight = 64,
      folder = "images"
   }
   map:setup(config)
end

function love.update(dt)
end

function love.draw()
   map:draw()
end

function love.keypressed(key)
    map:keypressed(key)
end

function love.keyreleased(key)
   map:keyreleased(key)
end

function love.mousepressed(x, y, button)
   map:mousepressed(x, y, button)
end

config = {
      tilewidth = 128,
      tilewidth = 64,
      folder = "images",
      sortFolder = boolean, -- optional, default false
      defaultTile = number -- optional, default 1
   }

Grab it and give it a spin on [1].

There is also a demo there. Enjoy!