Couple of Questions dealing with 2.5D

Alright, bear with me on my questions...

1.How can I go about rendering a 2D sprite/sheet on a 3D plane? I don't want the sprite to BE 3D just be able to walk on 3D terrian(Think Paper Mario).

1. tried SpriteManager, but it's for solid 2D which I don't want(someone can correct me if otherswise)

2. tried This script here but my image looks blurry when resized and I don't know how to go on about to make the character walk, etc with code using that script.

Anything that helps me get a result something along the lines of Paper Mario I'm fine. Tutorials dealing with what I mentioned is also fine.

Notes:I'm broke, so I can't afford any sprite Unity package import or anything of the sort. I suck at coding so I can't come up with anything... I searched all day looking for scripts that work for me... Thanks in advanced, hope I'm not asking for too much.