Cant honestly say I've heard of Silo, but I'll look into it for future projects.
There are tons of great software out there for the art. I use AC3D, which is a brilliant and easy program to work with (even for beginners) I've successfully constructed simple and basic models for 3D game design and code testing (including levels, player meshes, items, etc)
fun times, but such art still and always has required a great deal of patience.
and to answer the other mate's question: My mother accounted to me that I've been drawing since the very feeble age of 3. Simply put, I doodled on anything I could ever get my hands on because I was fascinated with my own imagination and creativity. =)