I would also recomend wings too it is a quick intuitive modeler. Silo is a excellent low cost option that has a lto of features that can get yrou feet wet with different techniques like it does  sculpting and face by face modeling. if you know wings then open up silo it will be somewhat familiar and you can get started.

Modeling is up to how you want to approach a problem how to approach how to make a shape. Some people are more inclined to spline type modeling others like to go the Z spheres/metaball approach others like box modeling.

Box modeling is taking a simple shape and adding cuts and extrusions until you get the shape you want. Wings is a good example of a box modeler

Spline modeling is more like cad type of work you make curves and trims etc. to get the shape you want.

Face by face modeling is a bit slower in sme respects but often needs less rework you make one face at a time. Silo and Metasequoia can do this

Zsphere and metaball modeling is done by taking primitives and they flow together at close range. Z brush does this also a lot of full featured programs have this feature.

Sculpting is done by different brushes and virtually sculpting the form to make a high poly mesh some allow you to make a low poly version adn then apply normal maps. Z brush and Mudbox are examples of this.

Now there are a lot of choices and there are some programs that do it all but do some things well and others not so much . My advice is learn a bit on the free ones then try out a few demos of regular modelers to see what you like before you put down the cash. Spending 10,000 dollars on programs does not make you a better spending time with the programs you have and learning them makes you good.

Personally I started with Strata 3D then went to Amapi then to Metasequoia now i use wings might get silo once I can scrape up enough cash.

The wit of a misplaced ex-patriot.
I cheated on my metaphysics exam by looking into the soul of the person next to me.