Hi,
Good points above and all aspects you'll need to take into consideration. The point I often make on posts like this (usually in the Transport section!) is that insurance quotes vary from different insurance brokers and underwriters etc. Also the type of car you are insuring makes a big difference as well. From there, secondary aspects such as if the car is garaged overnight, on a driveway or on the street will make a difference. If you have an approved immobilier or alarm make will affect your premium too. If you want to use the car for commuting as well as social, domestic & pleasure or if it's just social domestic & pleasure with no commuting. Elements you can't really control will be the postcode you live at and your occupation which will also affect the premium.
So, I suggest you ring around all the usual places you see all over the media, then ring up a few local brokers. If the car you wish to drive is perhaps larger engined or a more desirable car etc, then for a 'new driver' as you'll be classed as once you gain your UK licence, insurance costs are/will be high. The only way around this is to change your car to a smaller engined / smaller sized car.
If the car you want to drive is an 'interesting' type of vehicle, say a classic or american car or an import etc etc, then you could use specialist insurance brokers who specialise in these sorts of cars.
You'll have to look at all those variables and then look at the kind's of premium quotes you get from as many insurance places as you can. If you are finding that still too expensive, you'll need to look into changing the car to a less expensive one.
Cheers, DtM! West London & Slough UK!