Large Planting Containers (N. Lakeside in Henrico)

I am starting a container garden this year to experiment with growing food while we are renting, and I already have some tomato and pepper seedlings inside getting bigger every day! The books I am using suggest that a five-gallon or larger container be used for each plant, so I was wondering if anyone had something that size lying around. The containers will be well-hidden in the backyard, so they can be ugly! Maybe a bucket, plastic pot from the nursery, storage container with missing lid? Anything helps! Thank you so much. :)