In my mind, SQL along with PROC SORT, falls into the category of "SAS programming" more than reporting. Even though I know some folks use SQL for reporting -- I'm more a practitioner of PROC REPORT, PROC TABULATE and DATA step for reporting.
For general SAS programming questions, the SAS on-line documentation is a great place to start. The SAS sample programs are really very good. If you are using SAS Display Manager for your programming, there is a Quick Start Guide that you can access (on Windows, at least), that I have been told is quite handy and informative. In addition, there are Self-paced e-learning modules on programming available through SAS publications.
And of course, there are all our training classes. I think the issue of NODUPKEY and PROC SORT is covered in chapter 6 of our Advanced Programming class. (But we do not show an SQL alternative to PROC SORT in that class because of the "apples" and "oranges" aspect of the comparison. Proc SORT does one thing --sort data; while PROC SQL muddies the waters with the ability to select columns, create columns, order columns, group columns, etc all in one fell swoop.) The use of the DISTINCT keyword with PROC SQL to eliminate duplicates is covered in the SQL class that we offer.
But, I digress, you wanted to know about setting up a basic discussion forum. If you go here, you can enter a suggestion on how to improve the SAS Customer Support Web site: http://support.sas.com/contact/intro.html .