French Dart stuff
I used the instructions on modifying darts from Fit for Real People. If you use darts in your clothing (and I think you should unless you are male or a female with a cupsize AA or smaller; not on everything, mind, but a bust dart adds a lot of flattering shape to a garment), this is the best reference out there. However, they are not hot on french darts, which are french because they take their shape from the french curve, not because they are from France. In fact, the comments they make are discouraging.
I copied the french dart from a burda magazine pattern. The top I sewed from that pattern looks ... well, not terrible, but not as good as it could. I think the altered Kwik Sew t-shirt looks much better for a variety of reasons related to and not related to the french dart. Of course, this was only a starting point for the dart because I had to make it bigger and longer. I'd recommend browsing Burda patterns for a french dart sample. If I run across one still in print, I'll post here about it.