I am not entirely sure about getting an annulment to receive the Eucharist, but if you were not a Catholic at the time you got divorced, you have been forgiven the moment you receive full absolution at confession or baptism.
In truth it is not an annulment which allows a person to receive the Eucharist, but seeking forgiveness from God if you were the guilty party and then receiving absolution from your priest. That is if you were a Catholic at the time. Annulments in themselves do not grant forgiveness of sins at all. It is only through contrition and penance that one can receive forgiveness.
I have always thought Catholic annulments were simply a Catholic divorce on paper, but God knows the situation irregardless. I don't know when the practice of annulments came to be in church history, but I be willing to bet dollars to donuts, that no such thing existed in early church history. Marriage back then, was for life.
I will conclude and say this. Whatever and wherever your situation. God knows where you are at. He knows your whole life. If you know you were the guilty party then seek his forgiveness. God is not willing that any man or woman should perish, but come to repentance. When you receive that forgiveness, THEN you can receive the Eucharist. :)