You will need to book a flight to Malaga.
You may wish to ring or call in at your local travel agent
Alternatively, you can ring

British Airways 08457733377 (24 hours)
(Their prices are sometimes very high, but sometimes comparable to charter companies
Their dates can be more flexible.)

These airlines do not use agents, and should be phoned direct:

EasyJet They fly from Luton, Gatwick or Liverpool to Malaga. They prefer you to phone 08706000000 for bookings within the month and to use easyjet.com for bookings after one month.

Other ways of getting to Marbella

It is quite possible to go overland. Here is one way.
Take the Eurostar to Paris.
Take an overnight sleeper from Paris to Madrid (or Barcelona),
then take the train to Malaga.

There is a ferry from Portsmouth to Bilbao.

It is also possible to fly to Gibraltar.

Do book early and do be careful of school holidays including half terms when seats go quickly.
We can hold your reservation for a few days while you are sorting out your flights.

Don't believe the first answer you get from your travel agent - especially when they tell you there are no seats left.

If you keep ringing elsewhere you will find cheaper and better deals.
Good luck!