Please let me know if I understand your question correctly. Are you asking, where can you find the PicURL column in Turbo Lister?
If you're trying to import your listings into Auctiva using Turbo lister, you can do so by using the Turbo Lister File Exchange Format file. Log into your Auctiva account and this page https://www.auctiva.com/listings/upload.aspx
shows you step by step instruction on how to do that. Once you've exported your listings from eBay's Turbo Lister app, in File Exchange Format, you'll be able to open that file and locate the PicURL column.
Let me know if that helped.