Praise be to Allah.
First of all, we thank you for your trust in this site. We feel that your sending this message is indicative of your openness to searching for the truth and not to cling blindly to that which you grew up with. This in itself is a blessing and we ask Allaah to complete it for you by bringing you to the truth which will bring you happiness in this world and in the Hereafter. In order to reach that point, we advise you to read about Islam on this website and to think about it, and to be sincere in your search for the truth. Ask the One Who created you from nothing to guide you to the correct path and the right religion. Note that human life cannot be good and proper without a correct religion to give life and that this human soul cannot be stable without a proper relationship with its creator, Allaah. Worship of Allaah is the spirit of life, without which there can be nothing but hardship and misery.
With regard to your question about your getting married to a Muslim, if you embrace Islam and accept it as your religion – and this is what we ask Allaah to help you to do – then there is nothing to stop you from marrying him. Your guardian for the purpose of marriage should be your closest Muslim relative; if you have no Muslim relatives then your guardian should be the Muslim judge (qaadi) in the city in which you are living, or someone who is responsible for the Muslim community if there is no Muslim qaadi or sharee’ah court.
You should note that Islamic law (sharee’ah) forbids a Muslim woman to marry a non-Muslim man, no matter what his religion is, and it forbids a Muslim man to marry any non-Muslim woman apart from women of the People of the Book, namely Jews and Christians; no others are allowed. Allaah says (interpretation of the meaning):
“And do not marry Al-Mushrikaat (idolatresses) till they believe (worship Allaah Alone). And indeed a slave woman who believes is better than a (free) Mushrikah (idolatress), even though she pleases you. And give not (your daughters) in marriage to Al-Mushrikoon till they believe (in Allaah Alone) and verily, a believing slave is better than a (free) Mushrik (idolater), even though he pleases you. Those (Al-Mushrikoon) invite you to the Fire, but Allaah invites (you) to Paradise and forgiveness by His Leave, and makes His Ayaat (proofs, evidences, verses, lessons, signs, revelations, etc.) clear to mankind that they may remember”
This verse makes clear the great wisdom behind this prohibition, which is to protect Muslim men and women from being influenced in religious matters. But because the man is the one who has the final say in the household, he is less likely to be influenced by his wife than in the opposite situation, hence he is permitted to marry a woman from among the People of the Book only [not from other religions], because their disbelief is less serious than that of others, in general, and because they are followers of a previous divine message, even though it has been distorted, so they are different from others. On this basis, it is not permissible for a Muslim to marry a Sikh woman unless she becomes Muslim.
Our advice to you, to which we hope Allaah will open your heart, is that so long as this issue exists, you should make the most of it so that it will be a motive for you to enter Islam, especially since this Muslim man is following his religion. We hope that if you become Muslim, you and he will be able to help one another to be patient and steadfast, because after you become Muslim you will need someone to stand by your side and protect you from those who will not like the fact that you have become Muslim and have left the religion of your forefathers. This is how Allaah tests many of those who enter this pure monotheistic religion, so that it may be a motive for them to remain steadfast, and to show in reality whether they deserve this blessing or not. We ask Allaah to help you find the way to true happiness and to believe in it and adhere steadfastly to it, until it ultimately leads to Paradise as vast as the heavens and the earth. Please also see question no. 3023. Peace be upon those who follow true guidance.