Pricing varies by country and retailer; updated listings inside.
http://www.nintendoworldreport.com/news/24783
At Nintendo-Europe's 3DS event in Amsterdam, the company declined to advertise a retail launch price for the system, instead deferring to individual retailers. The major chains have now begun to reveal their plans for the launch price:
GameStop: 249.99 € (Germany, Spain), approx. $317 USD
Play: £219.99 (U.K.), approx. $351 USD
GAME: £229.99 (U.K.), approx. $367 USD
HMV: £229.99 (U.K.), approx. $367 USD
Amazon UK: £219.99 (U.K.), approx. $351 USD
EB Games: $348.00 (Australia), approx. $349 USD
Micromania: 249.99 € (France), approx $317 USD
Amazon: 249.99 € (France), approx. $317 USD
Komplett: 2299 Krone (Norway), approx. $396 USD
The U.S. suggested retail price is $249.99, plus tax. Many European countries have a value-added tax (VAT) that is included in retail prices, accounting for some of the cross-regional price differences.
I pre-ordered the 3DS on Komplett.no for 2499,- NOK which is approx. 433 USD, but they have lowered the price to 398 USD since then. Which is still a bit much imo but you won't get for anything less in Norway. :-[