If you snip off the shoots you will have lower production
what kid of help do you want ?

Side shoots (or laterals or suckers) have little to do with
the fact that your plants are setting few fruit.

How's the temps and humidity been in your area? Too hot
or too humid can keep flowers from setting fruit.

Duplicate post. See: http://forums.gardenweb.com/forums/load/tomato/msg0715043425743.html?2

Your plant is a determinate variety. They are never pruned. You can learn a lot about pruning, blossom drop, fruit set, etc. for the Frequently Asked Questions (FAQs) on this forum. I linked it below.

Dave

Here is a link that might be useful: Growing Tomatoes FAQs