Sorry I didn't reply til now. I missed your post earlier. I can see you figured out the weight tracker.
As for supportive friends, my best advise is for you to find a team of people on here that have similiar interests as you. As you get active on that team, many will start to interact with you on a daily basis.
There are many "challenge" teams also, that go for a certain period of time. I'm on one right now that runs for ten weeks. There are a different group of people on each time, so I've met many people that way - all who have the goal to lose weight.
There is also a "buddy finder". If you click on the Community tab, and then SparkPages, there is a place on there for you to fill in some information, and then find a buddy.
And for friends, check out the motivational pages, and add some of those people as friends. They will likely add you back, and you can follow along with their blogs and status updates.
There are several ways to connect here, and I've found that having friends to share this journey has made it more enjoyable!