They already did the auditions for Cho Chang and for Padma & Pavarti as well. Here are the articles concerning Cho:
http://news.bbc.co.uk/cbbcnews/hi/tv_film/newsid_3442000/3442617.stm - The advert
http://news.bbc.co.uk/cbbcnews/hi/tv_film/newsid_3468000/3468917.stm - The castings
The ones concerning Pavarti and Padma:
http://news.bbc.co.uk/cbbcnews/hi/world/newsid_3330000/3330159.stm - the advert which unlike the Cho one didn't ask for South East Asian girls but obviously that's where they come from.
http://news.bbc.co.uk/cbbcnews/hi/world/newsid_3339000/3339185.stm - The castings
Krum has been cast too - here's the info:
Potter casting directors have found the lad who will play Bulgarian Quidditch star Viktor Krum in Goblet Of Fire, according to reports.
A Bulgarian news agency says the lucky boy is indeed a Bulgarian, but he lives in London with his parents.
It said he was not among the hundreds of boys who queued up in the Bulgarian capital Sofia to audition for the part.
The report claims two boys from this audition were on the shortlist, but the London-based lad landed the role.
Forty six audition tapes from the Sofia casting were sent to film-makers in London, the report said.
"It was a tough choice because they were impressed by many of the Bulgarian candidates," said the man who organised the Sofia auditions.
The identity of the lucky lad has not been revealed.
Krum has an important role in GOF.
As well as being the star pupil at his school, he is Hermione Granger's love interest.
Shooting for the film, directed by Mike Newell, is set to start between April and June, and should be released at the end of 2005.
and this was the original news about the auditions in Bulgaria:
Bulgarian boys audition for Krum
Updated 05 February 2004, 14.00
Hundreds of 16 to 19-year-old Bulgarian boys have been auditioning for the part of Viktor Krum in the fourth Harry Potter film, Goblet of Fire.
Auditions for the moody Quidditch ace were in Sofia, the Bulgarian capital.
But we're not sure you'd want to be him - casting director Viktor Bojinov said he should be:"Not handsome but rather arrogant and repulsive on first sight."
The auditions are only one way the producers are looking for Viktor. They will consider British boys too.