Sales taxes in the United States are assessed by every state except Alaska, Delaware, Montana, New Hampshire and Oregon. Hawaii has a similar tax although it is charged to businesses instead of consumers. In some cases, sales taxes are also assessed at the county or municipal level.
In 1921, West Virginia became the first US state to enact a sales tax. Georgia passed legislation enacting a sales tax in 1929. 11 other states enacted sales taxes in 1933 alone. By 1940, at least 30 states had a sales tax. (info from Wikipedia)