I see that there is a similar question here: https://developer.salesforce.com/forums?state=id#!/feedtype=SINGLE_QUESTION_SEARCH_RESULT&id=906F0000000ArVTIA0
But it doesn't look like it was ever properly addressed.
It also looks like the interface for the back-end has changed a decent amount since then.

I found a good guide for starting PHP development:
https://developer.salesforce.com/page/Getting_Started_with_the_Force.com_Toolkit_for_PHP

But I can't figure out how to enable the API on my account nor how to retrieve the security token.

I see that there is a similar question here: https://developer.salesforce.com/forums?state=id#!/feedtype=SINGLE_QUESTION_SEARCH_RESULT&id=906F0000000ArVTIA0
But it doesn't look like it was ever properly addressed.
It also looks like the interface for the back-end has changed a decent amount since then.

I found a good guide for starting PHP development:
https://developer.salesforce.com/page/Getting_Started_with_the_Force.com_Toolkit_for_PHP

But I can't figure out how to enable the API on my account nor how to retrieve the security token.