If I have a Google Map on my page, how do I draw a "circle" around it with a radius and a blue dot?

var newloc_options = {
                                zoom:15,
                                center: results[0].geometry.location,
                                mapTypeControl:false,
                                mapTypeId: google.maps.MapTypeId.ROADMAP,
                                scrollwheel:false
                      };
var newloc_map = new google.maps.Map(document.getElementById("newloc_map_canvas"), newloc_options);

Th开发者_JAVA技巧is is currently my code to draw a map. How do I put a circle with a blue dot in the middle? (and a certain radius?)

I'm using V3 , and I have no clue where start.

Check the documentation

// Add a Circle overlay to the map.
            var circle = new google.maps.Circle({
              map: map,
              radius: 3000000 // 3000 km
            });