By taxi
Maxi taxis vans, known throughout the expat community as baisa busses ply the highway from Seeb to the corniche area. The charge is 100 baisa from corniche area to the church round about and another 100 baisa from the church round about to Wadi Adai.
On arrival at the airport, situated approximately 40km from the main Muscat CBD, you can get a baisa bus down the main highway in either direction.
The mostly orange and white taxis are a bit pricier, and they hang around the hotels where they get juicy fares from unwary travellers. They will charge 8 Rials for an airport trip if you don't haggle, but you should be able to barter for 5 Rials. They always say they will give you "good price" but its best to figure out what you want to spend then agree before you get in.
The Maxi Taxis ply the main routes through town, and they go where they want so you might have to find one going your direction, once you are on one, they will make sure you get there. THe place to wait for them is on the on-ramps of most of the main highway junctions, you'll usually see a few people waiting around for one. A journey within the Muscat area should not cost more than 300 Baisa each, but if you look like an experienced traveller and hand them 200 baisa then you can usually get away with that.
By car
There are many rent-a-car services available in the city. An international driving licence is required for renting out a car. Most of the Car Rentals have offices at the airport arrivals terminal.
ABC
Al Maskry Rent-a-Car
(http://www.almaskry.com/r...)Avis
(http://www.avisoman.com)Budget
'National
Europcar
Hertz
Sixt
Thrifty
The cheapest car hire is about 11 OMR 14 GBP for a day which will get you an economy car with manual transmission and sometimes no air-conditioning. To get yourself properly equipped, you should hire a 4WD which will be around 30 OMR 38 GBP. Make sure that you will get a proper induction on driving in Oman.
Road signs in Muscat can be quite confusing, particularly when having to decide which exit to take to reach your destination. Best to ask a local to provide you with directions if you haven't been to your destination previously.