Here is a list of all the useful URLs on Salesforce.com.
As URLs change frequently, if any of the following URL is not working, please leave a comment with details and I will update the URL. Also if you come across any other URL that is useful for Salesforce.com, do let me know. I will include that URL in the list here.
Salesforce.com
http://www.salesforce.com
Salesforce.com Pricing & Editions
http://www.salesforce.com/ap/crm/editions-pricing.jsp
Salesforce.com – Salesforce Videos
http://www.salesforce.com/video/
Salesforce.com You Tube Channel
http://www.youtube.com/salesforce
AppExchnage
http://appexchange.salesforce.com/
Salesforce.com & Force.com Developer Resources
http://developer.force.com/
Force.com Technical Library
http://wiki.developerforce.com/index.php/Wiki
Force.com Platform Fundamentals
http://www.salesforce.com/us/developer/docs/fundamentals/index.htm
Force.com Workbook
http://www.salesforce.com/us/developer/docs/workbook/index.htm
Force.com Cookbook
http://developer.force.com/cookbook/
Force.com Discussion Boards
http://boards.developerforce.com/sforce/?category.id=developers
Introduction to Apex
http://wiki.developerforce.com/index.php/An_Introduction_to_Apex
Apex Home Page
http://wiki.developerforce.com/index.php/Apex
Force.com Apex Code Developers Guide
HTML – http://www.salesforce.com/us/developer/docs/apexcode/index.htm
PDF – http://www.salesforce.com/us/developer/docs/apexcode/salesforce_apex_language_reference.pdf
Apex Code Best Practices
http://wiki.developerforce.com/index.php/Apex_Code_Best_Practices
VisualForce Home Page
http://wiki.developerforce.com/index.php/Visualforce
VisualForce Developer’s Guide
HTML – http://www.salesforce.com/us/developer/docs/pages/index.htm
PDF – http://www.salesforce.com/us/developer/docs/pages/salesforce_pages_developers_guide.pdf
Web Services Home Page
http://wiki.developerforce.com/index.php/Web_Services_API
Web Services API Developer’s Guide
HTML – http://www.salesforce.com/us/developer/docs/api/index.htm
PDF – http://www.salesforce.com/us/developer/docs/api/apex_api.pdf
Metadata API Developer’s Guide
HTML – http://www.salesforce.com/us/developer/docs/api_meta/index.htm
PDF – http://www.salesforce.com/us/developer/docs/api_meta/api_meta.pdf
HI