Richard J. wrote:
As far as I remember, the last of those services, run by National Express,
was the A2 which ceased about 4 years ago. I suggest you look at
www.nationalexpress.com to see what's currently running, but it's not the
most friendly of sites. Alternatively, say where in central London you
want to travel to/from, and we can then advise further.

The buses run by National Express from Victoria have been replaced by stops
on their existing buses to points west of Heathrow. It's about a
half-hourly service on various bus numbers.

Theo