Erica Stainwright was born in 1932 into parents of unknown blood status. She either was home schooled by her parents or attend Hogwarts School of Witchcraft and Wizardry which she would've attended from 1943 to 1950. She presumably purchased her wand from the Ollivander family when she was eleven.
After she graduated from Hogwarts, She became rich selling supposed "cleaning" potions, such as Everklena, but fell into disgrace when it was discovered that these products actually spawned more mould and grime, which presumably forced people to buy more of them to try to fix the problem. 
Death and Post-Mortem
Stainwright died in 2001 at the age of 69. She was on a Chocolate Frog Card after her death and she was awarded 'Wizard of the Month' in 2007.
- Wizard of the Month (First appearance)