cuttings from tomato plants
 

I've got several different heirloom seeds of tomatoes and I was just going to start a few plants since we're going into winter and I don't want to plant all the seeds at once. In fact in the next few years I figure these seeds will be worth more than gold. Watch this interview with Steve Shanks of eFoods Direct:

All Roads Lead to Food - YouTube

But anyway, my question is, can someone explain how to get cuttings from a tomato plant to start a clone?

As the tomato plant grows you will get many suckers (yes that's actual word for them) that grow from the plant. Usually you would just clip these suckers off and dispose of them so your plant grows tall and strong. What you want to do is clip them put a little dab of clonex gel or something similar then place it in a small rockwool cube that's been soaked in water. Sometimes within a few days or within a week or 2 you will see roots growing out of the rockwool, time to plant.

Humidity is Key
 

I agree with what Stan was saying but depending on the region you live in it may be necessary for you to maintain a higher than ambient humidity level. You can achieve this by using a humidity dome. Cuttings are at the most fragile stage in their lifespan, being cut from their mother plant with no roots to uptake water. High humidity is crucial in the survival of your cutting while it forms it's roots.
Also when soaking rockwool, the purpose is to adjust the pH to 5.5 due to the naturally high pH of the rockwool. You can do this by either adding pH down solution or with a few drops of lemon juice.

Happy Growing

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