If indeed you are sure it is EB then the treatments for it are well known and discussed in great detail over on the Growing Tomatoes forum here. It is a very common problem. There is no "cure" but it can be controlled if caught early enough.

Basically it's remove all the infected foliage and begin a regular spraying regimen of the fungicide of your choice. In most cases the fruit will continue to ripen but are more prone to insect and sun damage.

Dave

http://forums.gardenweb.com/forums/tomato

http://www.gardenweb.com/gardenweb/query/Early-Blight

Should confirm it's early blight and post pictures. Most likely not much you can do. Pics would help.