You might want to try checking with your local Technical College. It is one of the required classes for a welding degree.
Hobart Institute of Welding Technology offers "Welding Technology & Blueprint Reading". See http://www.welding.org
http://www.machinist.org/army_welding/Ch3.htm
The above is an amazing well detailed file thats about 30 pages and free! well worth printing off and keeping in the ol toolbox. It covers weld symbols and more importantly gives full explaination of relevance! Giving you the ability to understand disputed or difficult to comprehend prints.
The AWS Library (online) also has a little powerpoint presentation that gives a nice little discussion of lines and views.