I don't know if I'd call it amazing, just three people who like to dive and have a good time - it's tough to find a job better than scuba tours for that.
Most of Kona's dive operators launch out of Honokohau Harbor, which is about 4 miles south of the Kona airport and 2-3 miles north of Kailua-Kona. There's bascially 4 miles of rock between the harbor and the airport, and 2 miles of rock between the harbor and town, so it's easy to find, but the nearest places to stay are in town and you will likely need a rental car to get around. Lopaka was right about stressing reserving a rental car - there is no/little real public bus system, the hotels don't have shuttles, the area's kind of spread out and there's more tourists than rental cars (they run out frequently when it's busy).
Kailua has lots of condos for rent, you can check out
..VRBO® is Vacation Rentals by Owner® Vacation Homes Rentals by Owner for that. There are a couple of nicer hotels in the Kailua area, the Sheraton and the Outrigger to name a couple. The Royal Kona Resort is reasonably priced and is an older resort (Hilton built it in the 60s) that has been in the process of renovating and is centrally located. For a clean, modestly priced hotel I usually recommend checking out the Kona Seaside. The King Kamehameha has long been a centralized fixture and it's supposedly going to be remodeled in the next couple of years. The major resorts are about 30-45 minutes north of the harbor up in South Kohala, it's mostly high end stuff up there, many of them are very nice. A couple of the resorts up north do have operators that dive out of their areas also. There's lots of other options in the area, coffee farms with rentals, B&Bs and such, within about 45 minutes or so of the harbor if one wants to get away from the crowds.
It's an interesting place.
Aloha,