Some excerpts from various areas online:
Save money buying gear by shopping in low sales tax states
Buy things in Oregon, Alaska, New Hampshire, Delaware, Montana
clothing is tax exempt in minnesota
Rounding out the top 15 states with the lowest sales tax rates—all under 5 percent—are Colorado at 2.9 percent and Alabama, Georgia, Hawaii, New York, and Wyoming, all at 4 percent. Missouri taxes at 4.225 percent, South Dakota and Oklahoma at 4.5 percent, and North Carolina at 4.75 percent.
California has the dubious honor of having the highest statewide sales tax rate at 7.25 percent. Indiana, Mississippi, Rhode Island, and Tennessee all have a 7 percent sales tax. They tie for second place. Minnesota trails right behind at 6.875 percent, followed by Nevada at 6.85 percent, New Jersey at 6.625 percent, and Washington, Arkansas, and Kansas at 6.5 percent.