One way Shawville ↔ Gatineau is $20.00 (the inter-MRC "Pontiac–Gatineau" fare); a trip that stays inside the Pontiac is $5.00. Pay with a reloadable Transcollines card (tap on) or exact-change cash — drivers carry no change. When you board you're handed a free transfer for STO or OC Transpo, so the connection on into Gatineau or Ottawa is included. Monthly passes are sold on the Transcollines fares page.
A single scheduled coach — if you rely on it for work, don't count on catching the very last run of the day if it's full or delayed.
The 06:09 runs all the way to Cégep Gabrielle-Roy in Hull, where you change to STO city buses (and on to Ottawa's OC Transpo). The 08:11 and 16:29 run to the Parc-O-Bus des Allumettières park-and-ride in Aylmer, also on the STO network. Coming home, the free transfer you were given works the other way.