I am from Canada
, but I do know that any lottery winnings over $10,000 in the USA are subject to tax in the USA. This should fall under 'other income' as it shouldn't qualify as personal income, business income or investment income. The only way it should qualify as one of those is if you were a professional poker player, which, by the sounds of it, does not apply to you (yet).
Of course, if you are not sure, there is PLENTY of literature out there - the IRS website should be able to help you further.