I tried a few solutions but wasn't successful. I'm wondering if there is a solution out there preferably with an easy-to-follow tutorial.
You have three alternatives:
This is a simple library for keeping iFrames sized to their content. It uses the PostMessage and MutationObserver APIs, with fall backs for IE8-10. It also has options for the content page to request the containing iFrame is a certain size and can also close the iFrame when your done with it.
https://github.com/davidjbradshaw/iframe-resizer
Easy XDM uses a collection of tricks for enabling cross-domain communication between different windows in a number of browsers, and there are examples for using it for iframe resizing:
http://easyxdm.net/wp/2010/03/17/resize-iframe-based-on-content/
http://kinsey.no/blog/index.php/2010/02/19/resizing-iframes-using-easyxdm/
Easy XDM works by using PostMessage on modern browsers and a Flash based solution as fallback for older browsers.
See also this thread on Stackoverflow (there are also others, this is a commonly asked question). Also, Facebook would seem to use a similar approach.
Another option would be to send the iframe height to your server and then poll from that server from the parent web page with JSONP (or use a long poll if possible).