There are news that Sony Ericsson Xperia X10 mini and Pro are coming after Mid-March. On eXpansys website X10 Mini and Pro will be available for sale on March 16.
Sony Ericsson X10, on the other hand, will be available through same website on April 22. The prices are in pounds and are little high due to pre-order. The official prices are expected to be lower than these prices.
In Euro Xpreia X10 mini will cost around € 330 and X10 Mini Pro will cost around € 420.