A variety of economists have been debating the role of fiscal policy during the Great Depression. Some of them (also here) seem to suggest that things would have been much different if income tax rates had been lower. Although many things can be blamed on income taxes, the Great Depression is not one of them.
The reason why it's hard to blame much on the income tax is quite simple: most people did not pay any. There was not even withholding in those days. You may have seen some reports about the "lowest income tax bracket" during the 1930s was rising, but that ignores the most prevalent bracket of all -- the zero percent bracket!
I have toyed with the idea of putting some blame on property taxes -- property taxes were hefty, but I don't yet see the mechanism.