Hi April try this one haven't downloaded and used myself yet but it looks interesting

http://www.gardendesignpro.co.uk/acatalog/free_garden_design_software.html

thanks Moon grower, i'd better try that later when Daniel, one of my other sons, comes back, Im not very technical! and he knows more about the software stuff than me, which wouldn't be difficult....

Well I have downloaded but not looked at yet. It is a freebee version of a fancy tool so, I guess, will not have all the bells and whistles! But probably fine for us normal gardeners lol