Help with my Masonry BBQ Project

[Xabia Jim]

I've been looking at the prefab BBQ's here and between the prices and quality I 'm now thinking about building my own version of one for open hearth cooking and for my paellas.

I'm thinking about doing a large (1 meter +/-) open work surface against a concrete wall. I talked with a friend about using firebrick on the wall and he suggested I should use a ceramic tile for the back wall surface so it could be cleaned. (are there special tiles for this?)

Here's my current thinking....

Concrete blocks for the base, keeping it about thigh high.
Build in a central ash repository under a steel plate..... so I can sweep hot or cold ashes into a central pit and clean it out later.
Put a firebrick layer on the flat hearth surface.
Put a second firebrick layer around the hearth edge for ash control.
Put firebrick or tile on the back surface of the wall.
Use a Tuscan Grill setup for BBQ foods and a paella stand for my rices.
Heat and eat....

Should I also include sides and/or a chimney? I was going to go without them to make the paellas easier....

Does anyone have pictures, plans or other ideas for such a project?

If you have one, post a picture for me, THANKS!!