The most important way to keep your costs down is to plan ahead. Making reservations for air travel, rental cars, airport transit, and any tourist activities well in advance will save you a substantial amount of money. Last minute changes are expensive.
Somewhat paradoxically, renting a car can save you money. Since many of the best deals (like supermarkets and inexpensive restaurants) are outside of the resort, being mobile can really reduce your other costs. With some comparison shopping, and booked well in advance, a week's car rental can be found for less than $165 (be aware of the 10% +$2/day tax, and check if your personal auto insurance or credit card allows you to avoid the overpriced insurance). There is a car rental office in the hotel, and countless others at the airport. One way to save money is to take advantage of these local offices and rent a car for only part of your stay. Another way to save is to split the rental among two or more people. Although I don't have any personal experience with them, the rates at Autolink seem particularly good.
If you don't rent a car, you'll have to take a taxi from the airport to the hotel. Fare is $47 one way, plus $1 a bag. Up to seven people can split the fare if they pre-arrange, so try to share with as many people as possible. Also, you'll be better off if you make a reservation ahead of time: (808) 845-9905.
The first law of eating on the cheap is to take maximum advantage of the meals supplied by the conference. Our current plan is to provide four continental breakfasts (tuesday-friday), three lunches (tuesday, thursday and friday) and a heavy-appetizer reception on wednesday. There will be numerous coffee breaks with light snacks.
There are ten restaurants in the Mauna Lani resort complex, but none qualify as cheap eats. Unfortunately, the resort is far enough away from the nearest non-resort restaurants that delivery options are slim. Here are a few places that might deliver to the resort. Call to find out for sure:
The closest cheap places are in Waikaloa Village. A good moderately priced option is Roussel's, which is a New Orleans style Creole restaurant. For really cheap, try the Aloha Deli, Bravo Pizza Pasta, El Gecko's, or the several fast food places in the Village area. There's also the Waikaloa Village Market for groceries. In the Waikaloa Resort (on the coast, just drive right through the gates) there's "Roy's", where you can get a very good meal for a reasonable (although not cheap) price. I think Roy's is the best value among the resort restaurants. Also in the resort is the "Kings' Shops" area with several fast food and sandwich places.
If you continue up Waikaloa road past the village, and turn left onto the Belt Road (also reachable from the Waimea side) there are several more good restaurant options. There's a very tasty Korean restaurant, Yong's Kalbi (885-8440), and a couple of good Hawaiian places, Don's Pake Kitchen (885-2025) and Hawaiian Style Cafe (885-4295), as well as the closest real supermarket, the KTA. There's also a MacDonald's and various other fast food places.
The next closest town is Kawaihae, to the north on 270. Unfortunately, the prices in Kawaihae also reflect the tourist trade, although they're a notch below the resorts. Try Cafe Pesto (Italian, good pizza, 882-1071), Tres Hombres Beach Grill (Mexican, 882-1031) or Kawaihae Harbor Grill (seafood 882-1368). Get reservations, because you're not going to be the only ones trying to avoid resort prices.
Waimea is a bit of a trip, and being in the mountains, it can be chilly and wet in the evenings. However, my favorite cheap eats option on this end of the Big Island is there: Ann Sutherland's Mean Cuisine. Ann Sutherland is the person who put the Mauna Lani resort on the culinary map when she was executive chef there. She left to open a catering company, which now has a small associated restaurant that serves interesting and generally wonderful food at bargain prices. There's a small sitdown area, but it's mostly a takeout place. Consider brining home two meals if you make the trip, and don't skip her awesome desserts. They're open early morning until early evening, although they are closed sunday dinner. Mean Cuisine is in the Opelo Plaza on highway 19 in Waimea, 885-6325. There are lots of other options in Waimea, including a German-Swiss place called Edelweiss and the famous Merriman's (although those two are not cheap!).
If, in your travels, you make it to Kapaau, you must try Tropical Dreams Ice Cream, which also serves light lunches. And if you go to Hawi (near the northern tip of the Island) do eat at the excellent and friendly Bamboo Cafe.
Discount coupons, early bird (and late night) specials and other good deals can be found in local magazines and newspapers like This Week Big Island, West Hawaii Today, and The Hawaii Tribune-Herald. Also, call ahead and ask about early-bird specials or other deals.
Another classic eating on the cheap trick is to cruise the happy hours for free or cheap appetizers (which are generally called "pupus" in Hawaii). Check the newspaper ads or ask at the desk to see if any of the resort's facilities are offering "Happy Hour Pupu" deals and load up.
Of course, if you are willing to drive to Kailua (other side of the airport from the hotel), then there are lots more options. A pretty complete listing of local restaurants can be found at planet-hawaii.com/kohala-coast/dining.htm
On the other hand, finding excellent lodging that is cheaper before and especially after the conference shouldn't be too hard, especially if you start early. Personally, I've had good luck with B&B's, although I generally stay with friends. A fairly complete list of lodging possibilities is available from the Hawaiian Visitor's Bureau. Camping is also a good cheap option, although park cabins and campsites are scarce and will be booked well ahead. There are a dozen county-operated beach parks and camping sites that dot the circumference of the Big Island. Permit and registration information, can be obtained by writing the Department of Parks and Recreation, 25 Aupuni Street, Hilo, Hawaii 96720; phone (808) 961-8311. Lots of information on camping options is available from the visitor's bureau.