Has anyone out there crafted blank trees for building custom specializations or Force powers? I'm cobbling something together in Excel, but something more polished would definitely be a nice alternative.

OggDudes app lets you make custom trees.

I do the initial work by hand on a (printed) worksheet created in Excel. Once I’m happy with it, I enter it into OggDude’s Character Generator for the final polished look.

Sadly, OggDude's Character Generator isn't an option to my knowledge, as I'm a Mac user. I've hand drawn them and they work, just looking for a more polished form if it was out there.