Not sure if this is where this belongs, but www.fertilityfriend.com is a great website for charting your BBT.  They offer a free VIP membership for the first 30 days and after that you can decide whether or not you want to pay $10 per month to continue with the VIP or just downgrade to regular charting.  You don't have to give any credit card info until you decide to buy it, so there's no worries about being charged before you decide.
 
If you're interested in seeing what a chart looks like, here's a link to my home page and my recent charts.  http://www.fertilityfriend.com/home/26e013
If you decide to join, I'd appreciate if you did so through my page since I get five free days of VIP membership for every person who joins through me.