Kobra,

Its saying there is an open <div> somewhere (but you know that.)

One way to track down the problem is to check the "show source" box on the validation screen.

You can then scroll through line by line. You can narrrow what you're looking for because all the "bof"/"eof" comments will show up. Using those you should be able to track down the tpl_?????.php files.

Another way would be to use admin and turn off the sideboxes and then turn them on one by one and re-validate until you find the problem.

You would also do this with the center column settings, particularly "whats new" "specials" and "featured"

Hope this helps.

Good luck