Well, you have to be sure you are calling the extra fields inside the loop where the listing information is assigned. This way it is availible for each listing.
Just to be sure we are on the same page, you are talking about adding extra fields to the results for category/toplistings/searchresults correct?
If you know the specific extra field and it is global across all listings you could modify the code found here to help you get it to the template. There isn't a very easy way of handling the dynamics of extra fields when you can have different ones for different categories and the fact that some pages show listings from various categories.
Code that does this for 3.0.15:
http://www.68classifieds.com/forums/...ead.php?t=2310
Original thread for this modification:
http://www.68classifieds.com/forums/...read.php?t=198