Cant find that item youve been searching for? Want to see if anyone is looking for an item your selling? Ebay has a page called Want It Now where as a Buyer you can type in the item you are looking for and see if anyone else has posted that item you are looking for.
You can even save the search and when that item comes on ebay, you will get an email to say its been listed. You can then either bid on that item or just ignore the message if no longer require or isnt quite what you wanted/priced.
It works the same as a Seller, just type in the item you are selling and see the results if people have requested that item.
Its handy as a Seller because you can look to see if anyone has posted a wanted item before you list. You can then message and show you item you what could be your Buyer.
With Want It Now you can describe it in more detail letting people know what your after or what your selling.
Here is the link as the only problem i ever found was finding the page (hence the Guide)... http://pages.ebay.co.uk/wantitnow/
Hope this helps as its a great feature of ebay.