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Some good quality brats, look for sales, or if your a Costco member. Can't go wrong with chicken either. Regular grocery stores have value packs for meats and poultry. For side I like to make this corn salad. I take fresh corn grilled on Weber and then cut the corn off the cob or par boiled or frozen par boiled, put into bowl, add chopped red onion, minced garlic. Then you can add any veggie you want. I use a jalapeno pepper (I like spice), chopped red peppers, fava beans and black beans. Then add S & P, diced up cilantro and juice of a lime, mix together and throw into fridge to chill. As far as other sides see what is on sale and then go with that. Baked potatoes, salads are great at BBq's. Grilled veggies, yum. Hope you have a great party.

Chicken pieces are, by far, less expensive than any other meat you can throw on a grill; Cheap hot dogs included! You can make even the most humble piece a masterpiece with proper marinades. You may not go for this suggestion but one of my favored grilled meats is liver that has been soaked in salted milk for a few hours; just don't overcook it!
Grill up some day old garlic bread.
Grilled veggies are an inexpensive side and can seem very upscale.
Macaroni salad can be made for a song and really fills the plate. The same is true of coleslaw.
Sangria is an excellent choice for drinks. An inexpensive wine can be stretched to go a long way and is so very festive.

Do the burger bar, ground meat is pretty cheap, get a bunch of different cheeses and nice lettuce and sliced tomatoes.

I vote for chicken too...right now our local store has leg quarters for .49/lb....you can't go wrong for that price. It's so versatile too....you can build a whole theme menu around it. I love to make a Cornell marinade....
1 egg beaten
1 c. vegetable oil
2 c. cider vinegar
3 T. salt
1 T. poultry seasoning
1 t. ground pepper
Mix all ingredients & marinate w/half the sauce for 30 min to 24 hrs. Use the remainder of the sauce to baste the chicken while it's cooking.

buy a couple of whole chicken and butterfly them, marinate in lemon juice, olive oil salt and pepper and whatever your fav hot sauce is, then grill. cheap easy and completely yummy with grilled veggies or a good pasta salad. (couscous makes a great salad with chopped veggies)

Grill chickens (beer can) or a couple of small turkeys (brined and with a little wood smoke).

Pork has been very low priced too. Grill some pork steaks or some shoulder roasts low and slow. Baste with a mop. Shred and sauce (Tex-Mex, BBQ, etc.) Heck- make one for tacos and one for pulled pork.
Buns, tortillas, pico de gallo.
Grill some corn on the cob. Make a big batch of baked beans, slaw and potato salad.
Slice up some tomatoes, cucumbers and celery sticks with a dip. Open a jar of pickles. Set out mustard and ketchups. Make some lemonade (kool-ade jazzed up with some fresh lemon), toss some beer in an ice tub and call is a picnic.

If you're really on a tight budget make the focus on sides (salads, slaws, whole grain or rice salads, beans or bean dips, corn, etc.)

Make small individual skewers and cut the meat into strips or cubes, marinate and figure 1 to 2 per person. If you make 16 kebabs and there are 8 people, they'll know you've made two/per. You can even intersperse the meat with vegetables and mushrooms to extend the meat. You can season chicken, turkey, pork or cheaper cuts of beef with a nice, garlicky Greek-style marinade to tenderize and add flavor. Grill a big platter of vegetables drizzled with olive oil and some fresh herbs and add some grilled pitas, hummus, tatsziki, tomato-cucumber salad, some olives and a bowl of crumbled feta cheese.

Microwave baking potatoes until tender but not fully cooked. Let cool slightly and halve length-wise. Pour a little olive oil and seasonings onto a cookie sheet with sides. Season the potato halves with garlic powder and seasoned salt. Lay cut side down into the oil , then flip them or toss to coat. Grill the potato halves and serve with toppings- cooked, crumbled bacon, chili, sour cream, shredded cheese, sliced green onions, french fried onions, carmelized onions. Serve with grilled corn on the cob, a marinated vegetable salad and some iced drinks. Cut up a watermelon. Done.

Serve wine spritzers to extend the wine and still have a fun, alcoholic beverage. Or fruit juice spritzers for NA.

Preportioning helps too. Set out foods in indivual serving portions (in paper cups, lettuce cups, cupcake liners, etc.) Use small plates.

Beer-can chicken. Grilled potato wedges. Grilled, halved tomatoes.

What happened? I'm at the Jersey shore, it's pouring and nothing is working!! Your BBQ is probably in granite, but I love the burger bar idea and I have done it on a budget. The fixings are done way in advance and you can enjoy your guests. You can serve regular burgers or California burgers/avocado and pork burgers/coleslaw are becoming really popular. In light of those whose don't care for potlucks I will quietly suggest that if anyone asks that they can bring the sides or dessert. Many of my friends love to contribute to a summer event like this. I hope you have lots of fun!

BBQ= Meat...poultry and fish need not apply.

"I would be reluctant to try to BBQ a large pork shoulder for eight hours in a Weber kettle. How do you maintain a constant temperture for that long on a charcoal grill, without charring the outside of the roast?"

Check out some of the Weber and kettle grill websites.
Bank coals on both sides in a half ring. Add 10-12 briquettes every hour (5-6 per side) and leave cover off for 10-15 minutes to let the new ones re-ignite. Recover and grill.

I'd defintely brine it too. So much extra flavor and moisture for the long process. Don't forget a mist, mop and finishing sauce too.
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Or just give it a good spice rub and put it in a hot oven to start a sear. Then reduce the heat and cook it low and slow until the pork is done.
bast or mop if desired.

You can get a pork shoulder for $.99/lb. Marinate with a dry rub overnight. The next morning, let it sit out for about an hour before you put it on the grill, just remember to salt it before you do. Prepare the grill like CJ McD said. I found that you only really need to do the coals on one side of the Weber, so you can leave a drip pan under neath the meat. Add hardwood charcoal as you need it...about every 1-2 hours ( and mop it at the same time, so you don't keep opening up the kettle and letting all the heat go) and don't forget to put an oven thermometer in there so you can maintain a constant heat of 325-350 degrees. Plan on an hour per pound. You'll know when the meat just pulls apart and has that wonderful smoke ring!

Veggie kebabs can help stretch your bbq nicely. They're a bit fiddly to prepare, but not bad if you have a friend or kid or two to put to work, and with a good marinade, there's a lot of flavor per buck.

(Where on earth is everyone finding meat of any kind for under a dollar/lb?! 80/20 hamburger with a use by date of tomorrow is still at least $4/lb at my local supermarket, and big packs of chicken thighs are $3+/lb. Pork shoulder? $4-5/lb. If I walk to the Trader Joe's in the next neighborhood, I can get a low-quality whole chicken for about $1.30/lb, but that's not always so convenient, and they don't even carry thighs, alas. Is someone hiding the cheap food in Seattle?)

I agree with Judes' idea. Kebabs are the way to go. The cheapest bbq I ever threw was for about $30 and I fed 20 people until they were stuffed and had plenty to spare. Plus you can have them skewer their own and it helps fill in some of the gaps of what-to-do-with-loitering-company :)