The Mountain Shop
Sells ski and snowboard equipment and clothing. also handles repairs and service to equipment. be warned that the location on the hill warrants a 15-20% markup over prices you would pay in town. it is recommended to get the gear you need in town unless absolutely necessary, or you have money to burn. located above the rental shop.
The Trading Post
Is a small bakery/convenience store that stocks food/drink, essential toiletries, and a modest selection of apex souvenirs. the trading post is also the only place to buy beer/wine/spirits on the mountain other than the bar. located in the bottom floor of the gunbarrel saloon. (http://www.gunbarrelsaloon.com)
There is not much to buy up at Apex other than food and your lift ticket.