Depends on how much you paid for the raffle ticket as far as withholding.
IF I am reading this correctly, if you paid more than $3.34 for the raffle ticket, and won $1,000, no withholding is necessary.
FROM
http://www.irs.gov/instructions/iw2g/ar02.html#d0e393
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2. Sweepstakes, Wagering Pools, and Lotteries
File Form W-2G for each person to whom you pay $600 or more in gambling winnings from a sweepstakes, wagering pool, or lottery (including a state-conducted lottery) if the winnings are at least 300 times the amount of the wager. The wager must be subtracted from the total winnings to determine whether withholding is required and, at the option of the payer, to determine whether reporting is required. The wager must be subtracted at the time of the first payment.
The requirements in this section apply to church raffles, charity drawings, etc. In the case of one wager for multiple raffle tickets, such as five for $1, the wager is considered as $.20 for each ticket.
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As for if the winnings must be reported by you, I think if you win a 5 cent goldfish at the school fair, under the tax code you have to report it.