When you first reach the listing creation page, you will want to set the pull down for the eBay site (in the upper right of the page) to eBay Motors US - Parts and Accessories or eBay Motors. Once you have selected the one you need for the site, you will then have the appropriate category options for your listings.
When you block a person, they can no longer invite you to a private message or post to your profile wall. Replies and comments they make will be collapsed/hidden by default. Finally, you'll never receive email notifications about content they create or likes they designate for your content.
Note: if you proceed, you will no longer be following .