I'm pretty new at this so please be gentle with me.
I have just started two websites with your excellent theme and both have unasked for widgets in the sidebars.
Luxwriters, running Atahualpa 3.4.9, has an RSS widget stuck in the right sidebar. It does not show up under Appearances>widgets and I cannot get rid of it.
Las Calles, running Atahualpa 3.5.3, has Recents Posts, Blogroll & Meta widgets showing in the right sidebar. I thought I'd be clever here and try to do the two negatives make a positive thing and actually move the widgets (under Appearances>widgets) that claim to be there to the right sidebar. What happened is the unhappy disaster of instead of getting rid of the left sidebar widgets, I accumulated three more undesired widgets in the left sidebar: Categories, Archives and A sample text widget.
I removed the offending widgets from the right sidebar and it is now shows as empty under Appearances, but now I have TWO sidebars with supposedly non-existing widgets.
I'm really stumped and now I have widget fear. Please help.