Many are new to aromatherapy and must have heard about being careful with this oil. 1st, how do we identify if we are getting good quality essential oil (EO). I had learn to test the oil on a piece of paper. EO wil diffuse completely leaving no oil stain after a while. If the shop/maker try to use blended oil to pass off as Pure EO, you will be able to detect in this way. what you can do is, test the oil on a piece of paper and go on with your shopping at other shops, check the paper again and see how the oil diffuse off. Another way is to buy only from reputable shop of brand. I will recommend the following brands.
Jurlique
Aroma Vera
Tisserand
Evans
Natalie
Basic oil you can start with are
Lavendar
Eucalytus
Bergamot
Peppermint
Rosemary
Cypress
These oil has fragrance that are most acceptable and they can be mix and match with each other for very good results or use alone.
Some blend you can try.
Lavendar + Eucalytus - relax and decongest.
Lavendar + Peppermint - Migraine
Rosemary + Cypress - tired feet
Bergamot + Peppermint - Dizziness, nausea