I was struggling with the exact same problem, and this was one of the few Google-hits on your error message.
As far as I understand, what is happening is that the original LaTeXTools uses ST2's Python 2.7, while ST3 uses Python 3. So here's a solution.
- I had to start with a Sublime Text 3 (ST3) installation completely free of any LaTeXTools installation.
phyllistein's unofficial port of LaTeXTools for ST3 using
git, placing it in
Sublime Text 3/Packages. (In the terminal go to the correct folder and type
git clone https://github.com/phyllisstein/LaTeXTools)
- If needed, restart ST3.
TeX ahead! Please note that if you update this plug-in via Package Control before an official release of ST3 support, you might reproduce your original error message.
EDIT: There's also another plugin for Sublime Text 2/3: LaTeXing. Haven't gotten myself around to try it, but it looks promising =)
EDIT 2: I have now ported completely to the LaTeXing plug-in. It is awesome!