Here goes. I have not been satisfied with the "saved searches" built-in to eBay. The daily summaries were not timely enough. So I looked to ifttt. 1) Sign up for a free account here 2) Go to this link to see their different methods of eBay notifications I chose "Get notified when a new item is listed on eBay" and it has a little "works with (picture of an envelope, meaning email) in the lower-right corner. I had to have the search pretty well narrowed down in eBay already, but once I copied & pasted it over, it worked like a charm. I receive emails notifying me of new items that match my search filter pretty quickly... sometimes within minutes. Post here if you find a better method. Other "applets" involve SMS or smartphone apps that will push messages to you. Hope this is not old news. Cheers. P.S. This service can also be used for Craigslist and probably other websites as well.
For auction listings on eBay, I used saved searches to get email notifications as last second(s) bidding increases your chances of winning and at a lower final cost. I can see that newly listed feature helping a lot for relatively low priced or rare items being sold as a Buy It Now.
@physics-fan3.14, the saved searches only notified me once a day; this notifies me within a few minutes.