As far as a I know there isn't.
Aside from Google Earth - The two tools we use most frequently are
and TOPO USA buy it off ebay cheap...anything greater than 7.0 works AFAIK
In TOPO USA - you create a direct route between 2 points, then in the Show Profile window you set the "Ceiling" of the profile to the height of the tallest side. It sounds strange...but we'll take a ruler or sheet of paper or whatever and hold it up to the screen to see the "path". It's crude but....but it works for us. One of the nice things about TOPO is once you have all your APs in the address book doing a path analysis takes just a few clicks.
Be aware that neither one of these tools takes foliage into consideration...
Another tool that I haven't used personally but looks pretty slick is: