Ask Slashdot: Best 3-D Design Software?

An anonymous reader writes "I'm just getting into playing around with various maker-related tools, and I've run into a bit of a roadblock. I have access to a 3-D printer, a CNC mill, and a bunch of other fun tools, but I'm not able to make my own designs to use on them. I'd like to learn some 3-D design, but there are a ton of different software options, and I'm not sure which is the best. I've been hesitant to jump right into one, because I don't know how well it'll suit my needs compared to the others, and many of the options have a pretty steep price tag. I also don't want to spend a bunch of time learning one only to find out it's not very good for actually making things. I've played around briefly with Solidworks, Alibre, and AutoCAD, and also some free options like Blender and Sketchup. But these are complicated piece of software, and knowing nothing, it's hard for me to evaluate the differences. Makers of Slashdot, what do you recommend? Also, if you know of good online resources for learning 3-D design in general, or on any of this software in particular, I'd love to see it."