In order to change the order of blocks in your sidebar/left column layout you will have to edit the Catalog.xml file.

File Located: app/design/frontend/default/(Your Template)/layout/catalog.xml

In this file locate the left column : (reference name’”left”). Magento also does a good job at commenting out the blocks for you (refer to the comments). It is the “before” and “after” parameters that influence the order in your sidebar.