Yes, there is a fair bit of infrastructure to put in. Many places are putting in their own chargers, be it 1 or 2 designated spots (a couple of strip malls near me have them) or an entire parking lot of charging stations (like BCIT just installed). I live near Vancouver, so I am probably seeing a lot more progress than most of North America, but once its been proven to work in one city, others will follow. Where I live, almost all new structures are getting high-amperage cabling laid during construction to facilitate future charger installations (even private homes), so the infrastructure is already being built.
As for the cost of power, most estimates put it at around $3 for a full charge (from dead to 100%). For existing paid-parking garages, they already have the ability to charge for the parking spot by the hour/etc, so simply adding a flat percentage increase should take care of the cost of any power they consumed (just like the costs of maintenance and security are already included in the ticket fee). There are also chargers on the market that have built-in transaction systems for credit cards or coins similar to how a parking meter works.
I spot (without looking for them) at least 1 electric car almost every day during my daily commute (more if I drive instead of taking the train) compared to them being almost non-existent only a year or two ago.