rhollin1, welcome to the site.
There are quite a few different software packages out there that can serve your needs (<$100 sounding like the primary constraint), but truthfully, you probably won't find a lot of people here trafficking in that level of software, just because it usually can't do enough. So you may not get a ton of recommendations. We're getting our feet wet w/ Dynascape (one of our sponsors), and one can spend upwards of $4,000 for all the bells and whistles of their software.
This software is $40, I believe, and might give you what you're after.
As for landscape contractors being rip-offs or overpriced - every profession has it's share of bad apples, but you'll catch more flies with honey than w/ vinegar here (even if the first fly you caught may not have been the fly you were looking for
).
For a single DIY project, a pencil and paper doesn't have a learning curve and offers as much design flexibility as one can have. If it were me I'd take that software money and put it into bigger trees.