Personally I'm a Linksys fan - a
WAP54G would probably do you.
Don't forget that if even one client is using an old 11b adapter, the whole network will run at 11b speeds! What speed is your BT connection? Don't forget you and your colleagues will be sharing that connection, ie if there is a 10Mb connection to BT, having a 54Mb wlan isn't going to make much difference to browsing. The only difference will be to the internal file servers, if you have any.