Illlustrator help please!

[lawrenceots]

I need to make a 16 page A5 brochure in Illustrator - with rather short notice! I'm not sure what layouts or how I would actually go about getting this template - can't seem to get any information online. Thought it'd be under new document etc, but can't see to have any joy. - was wondering if one of you would be so good as to give me a little advice?

Much appreciated!