I'll be staying in old Monteal near the Palais des congrès for a convention later this month. I often like to self cater and make picnic lunches. Can anyone recommend a nearby grocery store to stock up?

I think the closest major grocery store is the IGA in the Complexe Desjardins (entry from within the complex or from the street at the corner of St-Urbain and René-Lévesque). There are also several small grocery stores on St-Laurent south of René-Lévesque in Chinatown.