Hi ginac84,
I use LinkedIn quite extensively and have found it to be a very good source of contacts and referrals. I haven't taken the usual path of trying to build a million contacts but rather I've focused on connecting to well connected people who I can then leverage into larger networks.
I've been able to re-connect with a lot of former customers and colleagues and I've also built some solid contacts around the world.
One of the best features I've found on LinkedIn are the groups - they have a lot of special interest groups.
I've recently started using a new UK based service called
WeCanDo.biz (
http://www.wecando.biz). As we're branching into the UK I've found this to be an extremely powerful and useful service