My tomato plants are growing like crazy and I had to find a way to stake them up. I have never been a fan of the cone shaped tomato cages you can buy at the Depot so over the years I have found a better way to support my tomato plants.
In a nutshell, buy a roll of wire fencing from your local home improvement store and fashion a round tomato cage. It is very easy to build whatever size cage you need to support your plants. I have found that the 4'x50' fencing works the best and will last for years if you keep them out of the elements in the winter time. Make sure you get the fencing that has the 2"x3" rectangular fencing for the best support.
Simply use some Lineman's wire cutters to snip off a 4' length of fencing. Then use the snipped side wire to wrap around the other unsnipped side of the cage to form a round cage. Then snip the wire on the top of the cage (this will be the bottom when you flip it over) to form little spikes that will be used to jam into the ground to help support the cage. That's it.
My wife and I made 8 cages this weekend for our tomato plants and the tomato plants seem to like the new support. I fully expect the plants to grow to the top of the 4' high cages before the end of the growing season. I will post a few pictures of the cage making process soon.