Here are two more pictures of the diseased tomato plant.

http://s52.photobucket.com/albums/g36/wheelterrapin/?action=view¤t=Tomato5.jpg

http://s52.photobucket.com/albums/g36/wheelterrapin/?action=view¤t=Tomato4.jpg

I think it may be verticillium wilt too Dave.
This is just a normal everytime disease i have to put up with here. I got one real bad infestation that came with seedlings one year and i pulled those plants out and burnt them.

However, for a not too bad problem, like Pauls' seems to be, i have reasonable success by removing all the damaged leaves and stems as they occur. Use sharp secateurs and have a jar of methylated spirit to continually clean the blades. After removing all the affected parts, and you'll have to do this more than once, give the plants a spray with bordeaux. You can use copper oxychloride too but i prefer the bordeaux.

Any blossoms that are open at the time of spraying, you may lose. But tommies produce new ones fairly quickly anyway.
As a result of the foliage being removed, it's possible that some of the developing tomatoes will be sunburnt on extremely hot days, so keep an eye out for that. Maybe keep a few scraps of shadecloth over the plants in summer heat extremes.
You'll have to keep this pruning and spraying up for the season, bordeaux will stay in place for quite a while but heavy rain will wash it off.
Once the plants are past their 'use by' date, you'll find you can't keep up with the wilt and you're best off to pull the plants out and make green tomato relish with the fruit.
Don't plant tomatoes in that spot, or other solanum family plants like potatoes, eggplant etc, for as long as possible. 5-7 years if you can do.
Also, you will need to discard/burn the stakes as the wilt will remain active in them and will be transferred to the soil where you use them next.
Not much good news for you but you should get a feed and the wilt can be managed with a bit of time and persistence.
Buy resistant varieties next season.

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The secret is the soil.