At the Hack for Change event I attended, one of the ideas that came from another group was a rain barrels for all kind of initiative. 250,000 rain barrels? Oh, yeah, since many houses have four downspouts like my house, maybe 1,000,000 rain barrels? For free? Then there's the installation. Plus, all the early-adapter hippies who will get angry they spent $50 a barrel and their pit-bull-owning, gun-toting neighbor is getting a free barrel that he'll just never hook up and use for bow hunting practice. Clearly, the only way to really create a rain barrel initiative is to not only provide them but also install them for people, and the whole process smells of raw sewerage, with logistical nightmares, profit-takers, and (frankly) lowering of property values. That said, you should have at least on rain barrel on your property.
I have two rain barrels right now, and I'm thinking of expanding it to four. However, since I don't have the $50 for the official Milwaukee-style rain barrel, I have so far used barrels I was using for vegetable oil storage. Any new barrels will probably be extra plastic garbage cans. With the drill and tap kits available, you can pretty much make the barrels out of any water-holding container, preferably plastic. My one barrel is steel. I went through an extra hole saw to put it together and it has had some issues with the area around the seal getting slightly bent (leaky), but you can use steel drums as well.
I'd recommend a stand for your barrel. I did not use one because I did not want my neighbor getting hot and bothered about the existence of two barrels right next to his house. Mine are pretty buried behind a bush, fence, and ferns that grow 4ft tall. If I expand the barrels to the other side of the house and front, this will not be the case, so the appearance of the barrels do matter. The official city barrels come in a whitish color that is supposed to be painted. That's not on everyone's to-do list. I'd say it's a victory if people will at least make the barrels house trim color.
As far as installing, I'd say the kits work fairly well for plastic containers. You need to bend the rubber spigot into the hole you create, and I've had some issues with leakage (one full popping off), but it's partially my fault, since I rigged up two barrels with one kit and some spare parts. The kit I use taps right into the downspout instead of having it drip onto a filter and then into the barrel. I like this because I have gutter guards and assume most of the water going in has been filtered of too much debris. Then, I don't have a lot of splashing and waste. I added an overflow hose to the top that sends water to the side yard, and I think it's important to have a plan for overflow, since these barrels fill up in one storm.
Whether you use an old barrel or garbage can with a conversion kit or a rain barrel bought from the store, you are helping reduce the amount of rainwater that travels back towards the lake. I don't think we'll save much (if any) money initially, since water is so cheap, and I don't think the city monitors whether or not we use the storm sewer less than our neighbors. We'll see if it makes a difference in the garden or on the grass, too. Maybe a little.
Main point is that it's not for everyone. My barrels have needed three leaks fixed already, one which would have drained all 100 gallons right onto the house. The setup takes effort, time, and money. They are not pretty, even if you paint them like rainbows. However, having at least one rain barrel is being a better citizen than not having one, and I need all the help I can get as I try to navigate right and wrong.