some general tips
#1: get a fixed dealer: The problem with rotating the deal is that what does the person who has the deal do when he has to check for blackjack? Now he has unfair info on the cards. If you try to remedy that problem by saying "dealer doesn't play that hand" then the dealer could be locked out of a crucial hand that could cost him the win. Grab a girlfriend or wife and bring her along.
#2: Buy a shoe: Get a 6 deck shoe, you can get them online for about 20 bucks and cards at about $1.50 a pack if you know where to look. It may seem like a pain but I would say shuffling once or less is better than shuffling 6, 7, 8 times.
#3: Buy some solid color chips: Ones without hash markings on the side, making it more difficult to count stacks, and adding another element of strategy to the game. You may already have these, if you do, use them.
#4: Look at various rules: Do you want this to be a low limit game? High limit? No limit? This will drastically change the strategy of your game. I suggest having the maximum bet be 1/2 of your starting bankroll, maybe a little more, and your minimum being 1 or 2 of the smallest chips.
#5: Considering splitting the group up: 8 people is alot for a blackjack tourney, and can get awful crowded. If 8 people were there I would suggest holding a bracket where it's 2 tables of 4, then the top 2 players from each table go on to the final table.
That's all I can think of for now. Also, if you charge a "house fee" for your poker games, do so for your blackjack games as well. This can help cover snacks, chips, cards, and what not.