When wood dries out, it shrinks and then leaks, so using wine barrels in the summer to catch rainwater probably is not going to work. I bought three plastic drums from a local company that was selling them for $5 each. Often things such as juice concentrate or other liquids are shipped in them. Ask around, someone in your area may be able to tell you who is selling them. Maybe if you indicate where you live, someone reading your post in your area may be able to help you out.

My wife recently read an article from the Vancouver, WA Columbian that stated that it was illegal to catch and save roof water runoff in the state of Washington. By law, all roof runoff must go to directly into the ground. What brought the question up was the fact that an architect for a new local government building had incorporated a system that collected the building's rainwater and used it for flushing toilets. Seemingly insane but Illegal!!