You can use any candle from anywhere :) You can even make your own. WalMart candles work just as well as candles from witchy shops. The most important thing is to just be aware of color symbolism. Like, you won't want to use a black candle for love, or a bright orange one for peaceful sleep, lol.
I would agree with everyone else, but I would like to add to what Ginseng stated. When you charge the candle and the anointing oil visualize them vibrating with the energy of your intent. For example, if they are to be used in a protection spell visualize them being encircled and infused with red protective energy. Visualize the energy moving inside of and around the candle and oil. Do this with all such spells, as it will help in it's fruition. At least I have found that it does so for me.
Thankyou for that input Calico :) i would also just like to add that you can also baphtize your candles with the elements , earth, wind fire and water this works particualy well when the candle is for a specific purpose/person. :)
Welcome. :) Ginseng, I don't know if baptize would be the best word. I think the word "charging" would apply here to, as I know of some spell preparations that involve using the elements to charge candles, crystals, etc.
Thankyou Calico yes your probaly right charging might be a better word to use , candles represent the fire element , passing the candle through the incence smoke would represent air, splashing water on candle would be water, sprinkle dirt/herbs would be earth :)