To add to what Paige said, reading other people's lucid experiences and DJs can help with motivation too. Also here are some good threads to check for goals and inspiration:
http://www.dreamviews.com/general-lu...cid-dream.html
http://www.dreamviews.com/general-lu...uragement.html
And competitions and challenges can indeed help, i am running dreaming competitions (roughly) monthly in General Lucid Dreaming class in DVA, so be sure to join in next one for inspiration if you want, whenever it starts.