
Primstar Sculptie Scripts by Domino Marama
Prim.Blender
-This is an offline building tool for creating SL objects in Blender. Basically, you create the object using various sorts of prims available in SL, then use a scripted importer (costs L$1) to put the object into Second Life.
Image Editing
Gimp
Paintshop Pro
Photoshop Elements
Photoshop
Other Sculpting Software*
Sculpty Paint
Wings 3D
+ Exporter and Templates
And more....
*I link to other sculptie tools to give possible alternatives to Blender, however, I cannot vouche for their quality nor ease of use.

Amanda Levitsky's Tutorials - Amanda's tutorials were where I started off. They're very basic.
Cinemacchiato Videos
- These are okay, but sometimes the explanations are hard to understand, even for me, and some of the techniques aren't as intuitive as I'd like.

$I have never personally used any in-world sculpting tool . However, from viewing several demonstration videos, I am convinced that none of these tools are as good or as fast as Blender and other 3rd party modeling software.