What John said
No one here is questioning your motives---but I've been on this earth half a century and have seen tournaments among friends deteriorate into fights and finger-pointing over cheating. IMO hosting an internet tournament--even if billed as a friendly one---is opening up a can of worms like you never imagined.
You ever win more than $600 at Foxwoods or the track? Remember what you had to do and fill out to collect your winnings? There's tax consequences here that you are ignoring. Maybe the IRS will ignore them too, or maybe they won't. If they don't, you could have some 'splainin' to do.