We've never offered print functionality for a radius search. It sounds like you might be referring to one of our comparable property pages like the one below. We don't show any active listings in Northridge right now but the link below will show you a recently sold home along with an overview of similar homes in the area. You can find more recently sold homes in this are at http://www.trulia.com/sold/Northridge,CA/ and if you click through to view more details for a property, you should find a link to view comparable properties on the next page.
Please note that you can perform a radius search on this page: http://www.trulia.com/sold/Northridge,CA/
Just use the dropdown menu under 'Search Within' to adjust the range. However there is no current overview page or for these search results that will allow you to easily print them all.
I hope this helps you. Please let us know if you have any further questions.