The two main points of entry into the United Kingdom are Heathrow and Gatwick. There are also many other regional airports like Aberdeen, Edinburgh, Southampton, Glasgow, and Stanstead.
All the airports above are owned by BAA. Within them you will find information desks that will be able to help you with any difficulties you might experience.
Things you should know about Heathrow:
It is the busiest International Airport in the world. An amount of people equal to the population of the United Kingdom fly from it each year.
If you are arriving or leaving from Terminal 4 you will need to allow for an extra 10-15 minutes as the terminal is a distance from the other terminals
You can get to the Airport from London via Underground for less then £5 or you can take the bus for a little over £5.
Things you should know about Gatwick:
Gatwick is less busy then Heathrow but slightly further away fron London.
You can get a train to London costing less then £10 or a bus for slightly less.