Tweetybird,
Dont bother to bring any electrical appliances to Doha. We have everything here. Not only is the voltage different but also the cycles and plugs.
For you hair, they have lots and lots of items at Carrefour & Hyatt plaza, Giant stores. There is also a specialized hair supply store on Salwa road called Nazih which sells everything professional incl dryers, irons flatters, products and whatever you might need. Dont worry Qatar has just about everything available here.
Aisha-Taweela