[TxMt] Help with bundles

I'm sorry if this is a totally obvious question, but I'm trying out Textmate after years of using BBEdit and I'm a bit lost.

I can see that there are built-in templates for XHTML documents, and in the bundle editor I can apply a quick-key to, I assume, create a new template, but pressing this key does nothing.

The whole concept of bundles and templates is really confusing. All I want to do is create a new document via quick key with some pre- determined text in it - how do I do this? Do I actually need to use command line commands to do this?

Thanks, Neil