If you are a C# developer and want to learn Salesforce here are some links to get you started.
You can create an unlimited number of developer accounts on Salesforce, Go to the developer signup page
Sign up for TrailHead, which is an interactive environment to learn Salesforce. Consider it like an advanced version of Channel 9
GoodDaySir is a weekly podcast just like .NET rocks covering the Salesforce world. Subscribe to it.
And don’t forget to use ApexSharp