The only cost for this is for five sheets of colored paper. About $2.
Staring with how it turned out (sorry for the crappy image quality).
Step 1: Make paper template
I used a perfect circle, 90- and 45-degree lines. And then I drew the holes for the eyes, lightly skewed for comic effect.
Note: this is not the actual template I used, but a fairly accurate reconstruction.
Step 2: Cut it out
So now I printed the three ghost templates on regular printer paper and transfered them to the colored paper (my ghosts are ~10cm wide). If I had a better printer I could maybe have printed directly on the stiff colored paper, but then I'd risk ugly ink spills on the edges.
Now I looked at the ghosts and scouted the cupboards for a plate that was the right size for pac himself, and outlined him on the yellow paper, drawing the mouth opening from the center with a ruler.
All left to cut are the eyes and the yellow dots pac eat. I used a reel of thread to get the right size.