it's the newbie again...

so I've been following a tutorial but as i deselected everthing at a certain stage i noticed there where some parts that were shaded oddly... so i think it's a bad mesh construction
how can i avoid these?
and once i have those, do i have to tweak around to get it right or is there a smooth tool instead of "smooth poligon tool" (cuz smooth polygon add verts which i don't want) that allows me to even these areas?
Edit: could post wreframe or other perpective if needed