I recommend organizing your transport from Cairo at the same time that you organize your hotel and desert tour. Most guides and travel companies can suggest a range of options, and many will simply pick you up from Cairo. You can get there easily enough on the bus (below), but it's not very comfortable, tends to run late, and takes longer than other options. If you're staying at the International Health Center, they can arrange a nine-seater minivan to pick you up and take you back to Cairo for between LE800 and LE900 ($145-$164/£74-£83) depending on whether you need air-conditioning.
By Bus -- The "bus station" is a kiosk in the middle of the town. If you've been wise, you've already booked a hotel, and there should be someone there waiting for you. If not, walk down to the main square (to your left with your back to the kiosk) to the tourist information office and talk to Mohamed Abdel Kader. He can help find you a hotel and get you to it. Don't worry if you find yourself being met off the bus and escorted there by a member of the tourist police. He's just trying to be helpful.
You can buy tickets back to Cairo or on to Farafra at the bus-stop kiosk. Bus times to Cairo are 6:30am, 10am, and 3pm. There is at least one more bus, around noon, but it's not possible to make reservations, and catching it, according to the ticket seller, is "by luck." Tickets are LE27 ($4.90/£2.50). There are two buses to Farafra: one at noon, one at midnight. The ticket is LE20 ($3.64/£1.85).
When planning your arrival and exit by bus, keep in mind that you're in the desert -- things happen when they happen. I recently took a noon bus out of town. It was nowhere in sight until 12:45pm and didn't leave town until well after 1pm.
By Car -- Arriving in Bahareya by car couldn't be simpler: Turn right off the highway just past the signs for the perpetually-under-construction Oasis Panorama hotel, and you're on the main street of Bawiti. The main square, where the tourist information office is located, is directly ahead of you, and Bayoumi's Popular Restaurant (a likely point of reference if you're meeting anyone in Bahareya) is down the first big street to your right. There are two gas stations in Bawiti, one of which often has gasoline.
By Foot -- There are no taxis in Bawiti, but for the most part it's small enough to get around on foot when you're not in your guide's vehicle.
By Car -- If you don't already have a guide and a 4X4 booked, ask at your hotel -- there are plenty around. Expect to pay about LE250 to LE300 ($45-$55/£23-£28) for the day inside the oasis.
There is really only one main street in Bawiti, and it runs through a central square. The post office, tourist information office, bank, and bus station are all very close to this square. The town sprawls outward, becoming older, lower, and more ramshackle in all directions until it peters out into the desert. None of the hotels, services, and shops listed here is more than a 15-minute walk from the main square.
The tourism office (tel. 38473039) on the main square is run by the helpful Mohamed Abdel Kader. If you're coming down from the bus stop, it's the office on your left inside the large, gray government building. Mohamed can help you find a hotel and get you to it. He also has pamphlets in various languages that list local hotels. The office is open 8:30am to 2pm.
At the time of writing there was only one place in town to access the Internet (the kiosk across from the police station in the main square, on the Bayoumi side of the main road). A six-station Internet cafe was under construction at the Western Desert hotel across from the Popular Restaurant, however, and this should now be in operation. Expect to pay LE10 ($1.80/95p) an hour for a slow connection.
There is a National Bank for Development, just past the main square on the right, open 9am to 2pm. It doesn't have an ATM, and its services are limited to exchanging currency.
Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.