Axes and sliding
http://img530.imageshack.us/img530/623/position1sd7.png You can move objects along their axes ( x, y and z)
The red axes is x, the green axes is y and the blue axes is z. If you click on any of the red, green or blue arrows - red arrow is seen in the diagram - you can slide it along. When you slide an object on an axes a distance ruler will appear to show you how much you are moving your object by, and the co-ordinates of that axes.
http://img515.imageshack.us/img515/6595/position2gb8.png You can move objects from square to square in the grid
By clicking on one of the triangle shaped, twin arrows in the corners of your shape (again, green, blue and red) the grid will appear. You can drag your object to any of the sqaures in the grid.
Other methods of positioning
As well as the methods shown above there are additional ways to position your objects, shapes and builds.
http://img407.imageshack.us/img407/9678/position4lw5.png You can type in the co-ordinates that you require in the position box, under the 'edit' tab in the build menu http://img530.imageshack.us/img530/9413/position3co5.png
http://img530.imageshack.us/img530/5135/position5oa9.png You can also use the 'move' tool to drag your object to the correct position