I am using Photoshop Elements and have downloaded a stock item but it is an AI file, not a psd. Any help on converting etc?
You will need to open the image in Adobe Illustrator or application that supports Illustrator files and convert it.
To convert an AI file, you need a compatible application Like Adobe Illustrator.
You can download the free 30 days trial of Adobe Illustrator from Adobe Creative cloud and convert your file accordingly by saving it in some different format.
Link to download: https://creative.adobe.com/products/download/illustrator
Please let us know if it helps.