The way I would do this is:
Create a Map class with a 2d array of Tiles.
if the player has free movement rather than tile movment, I would find the nearest tile.
I would then take that tile and center the camera on it. (basically translate the matrix to that position)
I would only render tiles that are within the camera position.x +/- Display.getWidth()/2 and camera position.y +/- Display.getHeight()/2
You might need to play with the render distance to make sure tiles that are half on the screen and half off are still drawn.
If you still need help tomorrow, I might be able to throw something simple together for you