Domestic flights in China are based on percent discounts from government-set full fare. The major international booking websites generally only price the full fare. To get local prices, sites such as Ctrip, eLong (owned by Expedia) and TravelZen are needed. See my China Booking Sites post for more detail.
These companies accept foreign-issued (non Chinese) credit cards with aggravating, constantly shifting policies. Failed transactions, long phone calls, need to dust off a fax machine have all been part of the process. Things are getting better, slowly. eLong now claims to have an online foreign credit card registration process.
Travelzen does not have foreign card fees. eLong I think still does but it is not showing tonight when I test as close to submit payment as I am willing to do. Ctrip’s website still charges 3%.
Ctrip now has an app for iPhone and Android that claims to accept foreign cards and waive their 3% transaction fee. I have not had a flight to book so have not tested it. I am not fan of booking via apps, seems too easy to overlook options or make mistakes, however for a simple trip already vetted online, it is nice to save the 3%. Hopefully it works.
As with many foreign airline web bookings it can be good to contact your card issuer in advance of purchase, especially when Verified By Visa and MasterCard SecureCode get involved. Just today I had a foreign airline website booking that failed even though I had called Chase in advance. Fortunately their Verified by Visa team was able to resolve.