Single and wanting another baby?

Single mother of one wanting to have baby number 2 as I'm completely finished with men, not interested in them in anyway. Yes I know it would ideal and lovely to have a partner/dad around but like I said I'm finished with men so no rude or smart comments. I'm just trying to decide if I should have another baby with my ex or possibly find a sperm donor for AI (which I'm scared to do honestly) or just forget it. I'll be 30 in 3years time & my current child is 9yrs old & would be lovely to have a sibling. I am financially stable