I originally learned with the Togood book as an exercise to go with the a class I took in college. The best book I have for the advanced features in PRO/E is actually the PTC course book for Fundementals of Design. However to get the book you need to take the class. I recommend the class if possible though because the surfacing, family table, and failure resolution parts of the class are good for those who just know how to do the basic modeling but aren't yet power users.
I ocasionally use the following sites for for help.
http://www.proecentral.com/
http://www.cadmin.co.uk/proehelp/
Also we have the online tutorial Cadtrain. It's really not that good though.
I think 90% of what I know in PRO/E came from learning the basics in school and then sitting in the middle of dozen power users for a few months.