I've been on there for a few years now and I keep finding more and more ways of getting better and better results.
Put these into action...
1. Make sure you profile is as complete as possible. Just get all your information, website, photo, and anything else that explains how you are the best at what you do.
2. Check out LinkedIn Answers and see if you can answer questions that people are struggling with in marketing themselves online. This way you can start to build a reputation as the go-to-man (or woman). Try not to come across as a smart ass though. No one likes those.
3. Link to your your LinkedIn profile from your blogs, websites, Facebook, business cards and whatever else you use.
4. Join local groups so you can be the person in your area that helps local businesses have some success online (or start a group yourself).
5. Keep your profile updated with news and recent business activity.
6. Share helpful articles or products with people for free.
7. Get people that you have done some work for to recommend you. This is one of the most powerful parts of LinkedIn. People take these recommendations seriously because of the business nature of LinkedIn.
Tell me how you get on and also add some ideas below of your own...