Auto Rigging Ready

Rigging, probably the least fun you can have. On par with UV wrapping in Maya. On creative crash website, you can search for free auto-rig scripts that can make the workflow ten times faster.

Advanced Skeleton

It is pretty well known free auto-rig. You can try it but personally, i have problems understanding it because i lack the patience. You can visit their facebook page to get the tutorials.

Other free scripts.

There are more free ones but some require you to buy to upgrade it.

Paid Auto-Rig Tools

The Setup Machine

I tried it and personally i really like it. It is efficient and easy to use. The skeletons and controls are created for you . On top of that, auto-skinning/weights is applied to your character. The rigging time is cut to just...10 minutes?

The only 'flaw' TSM has is that it doesn't do facial rigging. But there's the Face Machine.

The Face Machine

As good as TSM. Fast and surprising simple to use. Highly recommend for rigging and animation. Sometimes there are problems such as the eyes doesn't blink correctly. Well I can just use blendshapes to fix that area.