Hey all,
I'm hosting a 2-3 day training class on setting up & writing one's own RESTful WebAPI via Services 3.0. Full details can be found here:
http://groups.drupal.org/node/177079
The goal of the training is to start with an introduction to Services 3.0 & RESTful API development, then push past that with working 'template' modules distributed to class members, followed by guidance as you architect and implement your own authenticated RESTful API. The first 2 days should get one comfortable and working within Services 3.0, while the 3rd day is for individuals or groups that want advanced architectural and experienced guidance developing their WebAPI.
This is the fastest way to get up to speed with Services 3.0!