If you find yourself in Oxford St, you will discover Oxford Circus (a roundabout) and from that leads Regent St which in turn leads to Piccadilly Circus. If you walk down Regent St towards Piccadilly, on the left is Gt Marlborough St.It is only a short street, but along there to the left, in Argyle St, is the London Palladium and just off Gt Marlborough St to the right, is Carnaby St, the place where the Beatles and all the other '60's groups hung out. It's quite an interesting place to visit.
To continue down Regent St, you pass Hamleys, the largest toy store in the world.
At the bottom, Piccadily Circus, you can people watch before you take the short walk to Leicester Sq. this in turn leads to Trafalgar Sq. (National Portrait Gallery), and Nelsons Column on one corner is Pall Mall which leads to Buckingham Palace, PHEW!