Well along with the recent Toys ‘R’ Us power disc release, the GameStop and Wal-Mart pre-order for early release (Jack Skellington and Woody respectively), Amazon has started listing the Toy Story Play Set and and Frozen Toy Box Set as pre-buys.
Do note Frozen is a Toy Box Set, not a Play Set, which means on release they’d be like Jack Skellington and confined to the Toy Box. However, they come with both power discs to fully theme Frozen onto the Toy Box.
No release dates yet for the remaining Series 2 figures (Agent P, Phineas, Rapunzel, Vanellope von Schweetz, Wreck-It-Ralph, Sorcerer Mickey). What is known is Rapunzel, Vanellope, and Violet will also be released as the Girl Power Pack along with individual figure releases. Sorcerer Mickey was stated to release in 2014, but no exact date. Do note D23 Expo attendees already were able to get him and some placed him on Ebay. I would suggest waiting unless you just got to have him right now and have an extra $100 or so lying around.
UPDATE: fixed frozen product link