The Categories Images Plugin allow you to add image with category or taxonomy.
Use <?php if (function_exists('z_taxonomy_image_url')) echo z_taxonomy_image_url(); ?> to get the url and put it in any img tag or simply use <?php if (function_exists('z_taxonomy_image')) z_taxonomy_image(); ?> in (category or taxonomy) template.
Also from settings menu you can exclude any taxonomies from the plugin to avoid conflicting with another plugins like WooCommerce!
More documentation
Go to http://zahlan.net/blog/2012/06/categories-images/
