Tuff shed ontario serves the entire ontario, california area, including san bernardino, inland empire, san gabriel valley, los angeles, and riverside county. every tuff shed building is constructed with high-quality materials and includes free installation, innovative engineering and design, and industry-leading warranty coverage.. 2330 s castle harbour pl ontario, ca 91761 (909) 988-8833 ** please avoid doing business with this company**. i had the worse experience with this company. i requested several quotes for some sheds i'm interested in getting. i went to the tuff shed store in azusa and the store in ontario but these people are racist and show no respect..