in WW1, based upon this chemistry, carbin tetrachloride is no loner used in fire extinguishers, dry leanin, chemial reactions, toilet bowl cleaners
if you are referring to an alarm clock that you plug into the wall, the 9 volt battery plug is most likely used ONLY to keep the time. generally alarm clocks do to function on a 9 volt battery, it can only keep time with it. you probably can find the terminals where it plugs into the wall, but trying to hook up a pull chain switch would be complicated. the switch would need to be able to handle the amount of amps that is proved thru a wall socket. i wouldnt reccomend hooking one up to such a switch, but if you do take it apart, be sure you unplug it first!
You contact wholesalers. You buy products in bulk at wholesale prices, put pictures on a website, and sell at a profit. However, given that there are already gazillions of well-known children's clothing stores, both brickmortar and on-line, unless you have some very special items or gimmick, you're unlikely to make much money. (Why should buyer trust Natasha's Kiddy Clothes for tee shirts or dresses when she can shop at BabyGap or K-Mart or any of a thousand other stores?) Why not come up with a business that you are already somewhat familiar with?
