This is the Fiskars 55 gallon rain barrel that I installed with the help of my daughter, Kathryn (pictured). The water comes from the down spout (connection hidden behind my head). This unit has the advantage of being able to attach a garden hose. Although it comes with a plastic spigot I bought a metal one as it would be more durable.
I also constructed a platform using concrete blocks to make the barrel more accessible and to enhance the gravity flow which,, of course , is much less than what the pressure from city water would provide. At the end of the season the plastic tube that feeds the water from the down spout can be detached and the barrel can then be up ended for storage and protection from the snow.
Also note that the spigot is not at the bottom of the barrel. The weight of the water below the spigot acts as a anchor against wind.
Other rain barrels have the spigot at the bottom. They also have the over-flow spill out on the ground, but the Fiskars model is designed so that when the water level reaches the level of the intake it cuts off further in-flow from the down spout. Of course the intake tube has to be level with the place where the water comes in. This is all explained in the installation directions. The Fiskars model is available at Ace Hardware or at Home Depot for much less.