Part 2 of a two part update
Carry on north west between the Town Hall and the Pathenon (where the roundabout is shown in the picture above).
You see another small fountain, past a Tourist Information centre in the library. Then walk past McDonalds.
Come out the other side of the library and you should see the convention centre ahead of you as in picture below.
http://www.taglearning.com/downloads/98/brum%2 0wheel.jpg
Walk towards the conventoin centre, then go in the main entrance and walk right through the centre (try to see the Symphony Hall on your left if it is open).
Come out the "back" of the symphony hall and there is a canal in front of you. Cross the bridge shown here
http://www.birminghamuk.com/BrumFoto/brindleyp lace/iwe3.jpg
You are now in Brindley Place full of bars and restaurants, also the Sea life Centre, see picture below
http://www.birminghamuk.com/BrumFoto/brindleyp lace/brindleyview4.jpg
From here you can get to Gas St Basin and Broad St which are just yards away.
You can do this walk in reverse, start in Brindley place and walk towards the Bull Ring.
This is slightly easier as it is downhill all the way but I think it works better the other way.