There has been talk about removing Microsoft Office completely, since OpenOffice and Google has free "equivalent" products. My school district has already removed Microsoft Office from classroom student computers. Only teacher computers and computer lab computers have Microsoft installed. The future of Microsoft Office looks bleak! Their motto must be, "One step forward, two steps back!"
While most references to Clip Art disappeared with Office 2013, users were able to insert the old-school images into documents using an Office.com Clip Art option. That is now being replaced by Bing Images, with Microsoft filtering images to ensure they’re based on the Creative Commons licensing system for personal or commercial use. Most of the new images are much more modern, instead of the illustrated remnants of the past. Clip Art might be facing the same Office-related demise as the great Clippy assistant, but let the images below remind you of the good old times before the modern-era takeover.
If you mean your own artwork, then you'd take a picture of it, upload it to your computer (make sure you know where you're saving it), then select Insert > Picture in Word, browse in the location where you saved the photo, click the picture, and insert. If you mean an image from the internet or something, you can just save it to your computer and basically follow the rest of the steps above.
The download marketplace offers a variety of products and resources that you can download to create better documents and presentations. This download section contains add-ons for Microsoft Office like this Attachmetric that helps to tracks who has opened your emails and attachments or ClearContext Professional to prioritize, organize, color-code, manage Outlook in a better way.
This is TERRIBLE! Besides being able to edit vector images like Will mentioned (which is important for those of us who don't have graphic artists available to create custom images or the budget or time to buy that service ad hoc), you could also search for style "families" (different graphics that were all in the same style). There was a huge range of files and styles in the collection and it was much faster to find what you need than to do a Bing search. Plus, you knew that everything there was free and free to use, without having to worry about CC license issues.