Congratulations! You have a linked in account like millions of other. Besides having a few connections, you don't use the damn thing for anything. Don't feel bad. I want to help you.
1. When you accept a connection request start a conversation. It is easy to accept someone into your LinkedIn network and forget about it. That's what most people do, but you don't have to. Send a short message to introduce yourself. At first you will shock the other person because most people don't do this. But you are going to be different. Just because you are online it doesn't mean that good old fashioned human interaction can't help.
2. Check the connections of your new connection. After you have exchanged your message ask for an introduction to someone you want to connect with. If you see someone in their network you want to connect with ask for an introduction. If you ask for one introduction of every contact you have, you could easily double your connections.
3. Be active. Provide updates about you on your home page. I am sure you have seen "Share an update..." on the top of your LinkedIn home page. Use it. Tell people about what is new with you with your business. Did you land a new client? Did you open a new office? Did you move? Did you hire someone? Did you attend a trade show? Did you travel on business? There is a lot that happens even in a boring business.
LinkedIn is a great tool, make it work for you.