For content uploading check out mediafire. They have a video showing how to set up a free account and host your content there. You then just have to place a link on your page where people will click to download the material. Saves you space on your server and is easier in my opinion.

As far as content locking check out the cpa networks that deal in this. cpalead has videos as should the others. Although I am just starting to look at this style of cpa marketing I think the locker is some html you place on the page you want to lock. The locker is set up at the cpa network which then gives you the html code to copy and paste into your site.

Hope this helps.

cpalead has some tutorial videos, you can search the videos on youtube.

its very simple if your using WP u can add it in header.php file