Assalaam Alaikum Sister-in-waiting Shannonx,
In addition to the posts by my more learned Sisters and Brothers, who have already covered how you can address your Father's fears about your impending plans of reversion to Islam from Catholicism, just thought would add a few points that may inshAllah aid further.
I think you also have to keep in mind other factors to just religion. Your Father apart from of course not wanting you to; in his view, leaving the way of the Lord might also be facing personal and social pressures such as feeling a failure in keeping you on the "right path" and his standing in the community. Sadly name calling and whispers/finger pointing don't stop at our teens. As a catholic family and holding a firm belief in God I am sure he must see how your steps are not going against the Divine, but further empowering yourself to this realisation, but can he say this out loud in the current climate and go against his own life long held beliefs, his parents etc?
Another point you might want to keep in mind is that even after reading the Quran, watching the many videos on this site and as conveyed to you by Sisters and Brothers in their posts of reverted Catholics/ Christians, your father may never come round to understanding, let alone accepting your correct decision. As you must have read in the Quran; Allah say's there are people in this life that will never see the truth and are put here intentionally to try us. InshAllah your Father will not be in this league, but saying it as some comfort for you in that you don't start feeling disheartened, a failure yourself in not making your Father understand. If you look at it positively, your Father's questioning, stance are only inshAllah making your resolve stronger and helping in cultivating your own belief by covering one of the first points of Islam, the need for education and thus bringing out your faculties for reasoning, understanding and appreciation.
Lastly, I say the above Sister-in-waiting because you are white/Christian, think how it feels when brown/Muslim children face the same issues you are, how do they deal with it. You are not alone and should not just stick to resources for reverts, but any and all Muslim children faced with Parents opposed to their actions in taking steps towards Allah.
I hope the above brief points may aid you in approaching your Father differently and taking him away from his held arguments, leading to some progress in opening up avenues of understanding between you two, that can InshAllah be built upon to finally arrive at a mutually satisfactory outcome. It may just be you are pushing against a door that opens by pulling.
In the meantime, keep calling on all your Brothers and Sisters on TTI, who apart from prayers for you will do our best to answer/ ease your concerns/worries/sorrows.
Take good care, keep positive, speaking gently to your parents, respecting them and praying.
Fi amanAllah