If you view the POST REPLY form (not the quick reply form below) you'll notice I've been busy and have added three new icons to the right: amazon UK / amazon USA and play.
When adding links to items on amazon simply paste the ten digit ASIN number and the link will auto complete.
When adding links to items on Play you need to copy and paste the entire play.com url in order for the link to work correctly.
If anybody has any questions please ask. Feel free to try them out in this thread!