I’ve gathered a list of helpful links for reference and to help others. Comment if you know of other great articles, I will do my best to add them all.

PPC to CPA Introduction Articles

• CPA Marketing Series - Google PPC To CPA Introduction (CashTactics.net)
  

Affiliate Networks, Offers & Tools

• CPA Marketing Series - Networks, Offers And Tools Overview (CashTactics.net)
• CPA Marketing Series - Choosing The Offer (CashTactics.net)

Keyword Research Articles

• CPA Marketing Series - Keyword Research (CashTactics.net)
• CPA Marketing Series - Keyword Research Questions Answered Rd 1 (CashTactics.net)