The general procedure at YYZ and other Canadian airports is:

leave plane from international flight
Canada immigration
collect checked baggage (whether or not it is through-checked, you need to have it in case customs want to look at it)
Canada customs
recheck baggage
security to get into secure area of domestic terminal (may be slow)
run to domestic flight gate to avoid misconnecting

To specifically answer the question, after exiting Canada customs, you'll have your checked baggage, outside of the security screened area (but it is not at the baggage claim area for domestic flights).