Here are some Stata resources that I have found useful. Statistics with Stata by Hamilton is good for beginners although it is overpriced. For the basics I like German Rodriguez's free Stata tutorial best, good material can also be found at UCLA's Stata starter kit and UNC's Stata Tutorial; two page Stata is good for getting started quickly.
Christopher Baum's book An Introduction to Modern Econometrics using Stata is excellent and worth the price. The world is indebted to Baum for a number of Stata programs such as NBERCycles which shades in NBER recession dates on time series graphs--this was a big help in producing graphs for our textbooks!--so buy Baum's book and support a public good.
I have found it hugely useful to peruse the proceedings of Stata meetings where you can find professional guides to using Stata to do advanced econometrics. For example, here is Austin Nichols on Regression Discontinuity and related methods, Robert Guitierrez on Recent Developments in Multilevel Modeling, Colin Cameron on Panel Data Methods and David Drukker on Dynamic Panel Models.
I found A Visual Guide to Stata Graphics very useful and then I lent it to someone who never returned it. I suppose they found it very useful as well. I haven't bought another copy, since it is fairly easy to edit graphs in the newer versions of Stata. You can probably get by with this online guide.
German Rodriguez, mentioned earlier, has an attractively presented class on generalized linear models with lots of material. The LSE has a PhD class on Stata, here are the class notes: Introduction to Stata and Advanced Stata Topics.
Creating a map in Stata is painful since there are a host of incompatible file formats that have to be converted (I spent several hours yesterday working to convert a dBase IV to dBase III file just so I could convert the latter to dta). Still, when it works, it works well. Friedrich Huebler has some of the details.
The reshape command is often critical but difficult, here is a good guide.
Here are many more sources of links: Stata resources, Stata Links, Resources for Learning Stata, and Gabriel Rossman's blog Code and Culture.