Hi Stefi
I agree with May - it is in 'central London', but it's a big place!
The centre of London is surrounded by mainline and other railway stations - if you come from Gatwick airport, you will arrive at Victoria. From Stanstead, you will arrive at Liverpool Street and from Heathrow, you would probably arrive by 'tube', at Paddington.
The whole city (north of the river mostly) is covered by the underground train network, so from any of the stations I mentioned you can get to most places in a few minutes.
Victoria station is in the south-west corner of what is considered to be the main 'tourist' area, but it really depends where you want to go - it is ideal for Buckingham Palace, or for Harrods, for instance, and only about 20 minutes walk from the station to the Houses of Parliament and Westminster Abbey. Victoria is also London's main coach station for travel all over the country.
There are hotels in almost every street!
If you want to know about interesting places to go in London without spending a pile of money, just ask here!