Look at the xeriscaping forum for a ton of good ideas. Aside from that- I could only suggest cacti.

But hey- whadda I know- I live in Cow Hampshire

Here's a link to the forum.

Here is a link that might be useful: xeriscaping

Here is a short list of heat lovers:

Portulaca - very colorful
Lantana - very colorful
Sedum
Rosemary

These are all plants that thrive in the hot blazing sun and don't like too much tender loving care.

I live in a very humid area but I have spent a little time in your part of the world. While I totally igore these plants you may want to provide a VERY slow drip soaker hose. Don't give them too much rich soil or fertilizer though - they don't like it.

BTW, any of those plants can simply be snipped back if they get too bushy. When I trim back my rosemary I throw a couple of sprigs into simmering water to make the house smell wonderful.