You could write Bzzzz or Zzzz or any other buzzing sort of sound.
You write sizzle.
baaah
ting
squeak
BOOM!
bacock
The sound a whistle makes is often described as "whoo" or "wee" depending on the pitch and intensity of the sound.
"bzzftt"
dribble dribble
A drill makes holes in things.
BWAAAAAAAAAAAAAAAAAAAAAAAAA~!!! At least that's the sound he makes around here.
whoo ooh whoo ooh