SM have announced on their website that they’ll be holding a week of concerts for individual artists in Seoul between the 21st and the 29th for all their major artists.
EXO and F(x) will have a joint concert on the 24th and 25th December at the Kintex in Ilsan. Tickets can be purchased on the from http://ticket.gmarket.co.kr. For overseas fans, SM are setting up a tour package through their SM Travel website. At the moment it only says ‘coming soon’.
Tickets will go on sale from the 12th of November starting with SHINee.
Thanks to 
frantastic for the English ticket info. The Dream Maker website has the full list of concert details and ticket sale times (under board). It’s all in Korean.
Source: SM Official Korean Website
