A very merry Yuletide to all! I hope you are excited about what the new year will bring. For me, if all goes well, it will bring a working printer: at the rate I'm going calibration should start in January and real printing (knock wood) in February -- surely to be rudely interrupted by our upcoming move.
In the meanwhile, since I'll have some downtime away from Internet for several days around New Year's, I'm collecting some educational reading on modelling software - having learned that I can't effectively just try out a few things and then move on to complex tasks with success. So far, I've checked out:
OpenSCAD: OpenSCAD User Manual (printable version)
TinkerCAD: I have an old account but even after password reset I can't log in, and there are no significant manuals outside of it.
FreeCAD: FreeCAD Manual (printable version)
3DTin: Looks somewhat primitive in comparison with the above. Manuals only in video form.
MakerBot Customizer: Sounds interesting, but when I log in I hit a login loop :(
OmNomNom Creator: Only 2D to 3D conversion.
ModelBuilder (Mk2 seems incomplete?): Geometry library. Docs only in raw HTML form, fairly impractical on a ChromeBook.
Google SketchUp - I have tried it and found it initially useful, but prone to difficult gaps.
Sculptris: Possibly too artist-oriented for me, and doesn't have downloadable docs.
Art of Illusion: Aimed at graphics, but supposedly useful for design, too. Has a downloadable manual.
CadQuery: jQuery for CAD programs. Has documentation, but not in a readily downloadable format.
ShapeSmith: In-browser parametric CAD, but no downloadable docs.
Wings3D: Erlang-based subdivision modeler. Interesting concept, no downloadable manual.
123D Design: Commercial, but has a free version (I'd rather not pay until I have an idea what I should pay for). Only video tutorials, though.
...and many more. 3Ders has a long list but with no indication of which ones are the most useful for 3D printing, and includes a lot of graphics-oriented software. reprap.org's list is even longer. And even those are not complete. This is a big field.