when you list things on ebay, they do not always show up straight away, sometimes takes up to 12hrs for them to be searchable to any regular ebay user, i think its something to do with fraud and they probably check the adverts before letting them go live so everyone can see

it will work off the link you send to anybody, but wont be able to find it on the search function till its available on your sellers sale page.

so when you can see the car on this page:

http://search.ebay.co.uk/_W0QQsassZimpreza-sti-v5

everyone else will be able to see it too