Make better software series : http://training.fogcreek.com/
All the Articles by Joel : http://www.joelonsoftware.com/backIssues.html
Guerrilla Interview Guide ( One of the Classics of Joel ): http://www.joelonsoftware.com/articles/GuerrillaInterviewing3.html
Few Articles from Top 10 by Joel :
Mistakes you should avoid when writing software http://www.joelonsoftware.com/articles/fog0000000069.html
Building your own Company.. read this first : http://www.joelonsoftware.com/articles/fog0000000056.html