Here’s a Google Map of Zagreb: use the controls on the left-hand side to zoom in and out and scroll around.
Don’t forget that Streetview is now available in Croatia – drag that little orange guy onto the map to see what places actually look like! This may well be useful if you’re trying to look up a particular sight or place of accommodation.
Below the map, you can use the directions box to search for routes to and from Zagreb, and within the city itself. Helpful, if you’re trying to find your way to a particular place!