For human effigies, they are dropped by mobs (like dogs), but I find the best way is to just make progress. Additionally, in Dark Souls 2, you can be returned to human state if you help someone. It helps lessen the need for said effigies. Even if you run out, there is an area you can go to in order to restore yourself. Up to you to find it though.

I ended up just having a ton of life protection rings, once I got good at it I rarely died, plus they're cheap to repair.