My goal is to send an email to our firstname.lastname@example.org email address when someone fills out our contact us form. We were previously using sendgrid, but have switched over to using Salesforce Exacttarget.
Is this possible with the Exacttarget API?
As Adam mentioned, you will need to create an Email and Triggered Send Definition, then start the Triggered Send Definition. Those steps can all be completed in the UI instead of using API calls.
The only API call you will need to make is the actual call to initiate the adhoc single email send using the definition you already created: