need motivation, friends and fitness tips

Hello all I am kinda new at this weight loss thing. I have been what most fitness gurus call a yoyo dieter. I have joined MFP to become fit again one step at a time. I could use all the tips motivation and friends needed to get me into shape. I am a 100% daily logger and I am looking forward to losing 100 lbs and also need info on training for marathons. Any help will be gladly accepted.