For sellers with Selling Manager Pro, you can get a download of a CSV file of your Active items.
For sellers without SMP, you can use the relatively similar File Exchange Export.
If you have Selling Manager Pro:
1. click the File Management Center link on the left of your Selling Manager Pro page.
2. click the Create a Download Request link.
3. setup a download for your Active items.
If you do not have Selling Manager Pro: check out this guide on How To: Use eBay File Exchange.