I believe
@True Grit has done some scenarios and TLs dealing with this idea. Basically IOTL no one had a plan. Parizeau and Bouchard deeply distrusted one another and the Premier planned to make Bouchard a figurehead in the negotiations with Canada. Liberal ministers were questioning whether or not Chretien could stay on if he lost. The consensus was that if the Prime Minister couldn't reach a deal that kept Quebec or if he became a hindrance to the negotiations, the Liberal Party would force him out. My guess is that there would be a mini civil war within the party, with one side calling for another Quebec leader to help negotiations and prove to Quebec Canada still cared (Probably led by Paul Martin) and another wing representing English Canada and their interests (I'm thinking Brian Tobin).
Let's assume Quebec separates, which is no guarantee. Another referendum on either accepting Canada's new deal or going independent would probably be held. But let's say Quebec leaves confederation. Charest, Chretien, Martin, and all the other prominent Quebec politicians are gone. Martin might try for a seat in Ontario in an attempt to save the country or something, but my money is on Tobin as the new PM. Heck caucus might pick him as an interim Prime Minister and make sure there are no challengers for his coronation.
The clear winner from all this is Preston Manning and the Reform Party. They still got the west and probably parts of Ontario now since they're the main "Anti-Quebec" Party, and post-Independent Quebec there's probably some bad blood. Without Quebec Preston Manning could easily become Prime Minister, which is a death-blow to the PCs. But that's an assumption. Maybe in the midst of all this chaos Canada might be willing to give Joe Clark another go. Experienced, from the west but not hostile to building a relationship with Quebec, but who knows.
So a potential list
could go...
Canadian Prime Ministers
Brian Mulroney (Progressive Conservative) 1984-1993
Kim Campbell (Progressive Conservative) 1993
Jean Chretien (Liberal) 1993-1996
Brian Tobin (Liberal) 1996-1999
Preston Manning (Reform) 1999-2003
John Manley (Liberal) 2003-2011
Stephen Harper (Reform) 2011-
Geez think of that, Harper versus Manley. Now that's a boring election.