I developing a website that allows users to search for events in their
area. I want to allow them to perform the search and then return
abbreviated results if events matching their criteria are taking
place. If they want to see the detail of those events they will be
required to make a micropayment via SMS, or become a full subscriber
via paypal or similar. Having paid they can continue through to see
the full search results.

Am I right in thinking I require a content management system to handle
this? Is there a budget / open source off-the-shelf CMS that includes
this funcationality?

If not, I understand there are forums with 'programmers for hire'
where I can submit my brief and they will quote me on the development
required. Can you steer me in the direction of some of those?