Adding an entry to Yahoo UK & Ireland will mean that it's entered in the main Yahoo catalogue too, so there's no need to worry that your information won't be seen outside the UK.
It also seems likely that the huge lists of AltaVista, one of the most used search engines on the Internet, will shortly be available through a UK mirror site. AltaVista have already opened up a mirror site in Australia, to combat the long waits that Australian and New Zealand users faced because of the limited capacity of their link to the US. No official statement has yet been seen, but we expect to hear something shortly.