I need a publisist

I am an author who has made it to Barnes and Noble my sales have gone stagnet and little to no sales recently. But I would like a publisist. I will pay the publisist 45% of what the book makes. Since I don't have much money due to finiancial issues lately. (i will set the budget at the default it post but please remember I will pay a percentage of whatever the project makes so it will be constant pay for my next book and other books Ive made)