Best way to get to Brighton from London?

Take the train from Victoria Station.

http://www.southernrailway.com/index.php

As for cost, it depends on what ticket you wish to purchase eg. a cheap day return which start at £19.00 Return for an Adult Single.

You can check fares here -

http://traintimes.org.uk/london%20victoria/brighto...

National Express Coaches have a regular service which takes around 2 hours and costs from £6 upwards return. The service departs from Victoria Coach Station in London, but there may be other London stops.

http://www.nationalexpress.com/

Yep take the train, either Southern Railways for an express service from Victoria, otherwise First Capital Connect run from Kings Cross, Farringdon, London Bridge and Croydon to Brighton, but they're all stops so not as fast.

You get the best deals the further in advance you book, and can buy tickets before you travel on the Network Rail website

You can pick up the Victoria to Brighton trains from Clapham Junction which is good if you are not travelling from Central London. xx

By train from Victoria. Only just over an hour, and loads of frequent trains, so its dead easy to get to Brighton.