With Bob that I think this isn't really the right forum for in real life sexy time. But if you're looking for online stuff then there are lots of girls here who do domination.
As for where to send you to find that kind of service... If you have a partner I would recommend not being shy about discussing your fantasy, they might be up for it and it would save you from having to cheat to try it out. If not, then there's the option of looking for someone to date who shares your fantasy, I believe there are dating sites based around fetishes. This fantasy is one that is shared by plenty of women, and I think there are a lot of women who would be up for having a go simply out of curiosity and for thrills.
If none of these options appeal to you, perhaps because you don't want to put yourself out there or perhaps because you'd feel more comfortable your first time being with a professional, then there are escorts who offer this service. I have a friend who has the same fantasy and he spent a lot of money for escorts to do this before he got into a relationship. I don't know how much the going rate is where you are, or how easy it is to hire escorts. But in the UK there are agency websites and adultwork.
As someone who has engaged in anal sex, my only advice in this regards is to have a level of trust with your partner. Having a partner who is experienced could be beneficial as they will know to be more gentle at first, but definitely being with someone who understands you and how to read your signals. As much as being fucked really hard sounds awesome and looks really hot in porn, it is actually really painful if you aren't used to it and can cause all sorts of problems. A mistake many men make first time they engage in anal sex with them penetrating, is going too hard and fast immediately. I imagine that this is a mistake women could make too, especially as with a strap on they cannot feel what's going on.
Granted you may already be an experienced user of anal toys and butt plugs so may be less tight already, this will help. Anal sex can be really awesome, but it is also a delicate area which is not supposed to be penetrated, so remember to stay safe!