The date of this years Liverpool Marathon has recently been announced as Sunday 14th October 2012.
Full details from Run Liverpool site.
The course, (at present and subject to final confirmation), is the same as last year, starting in Birkenhead. It then goes over the Four Bridges to New Brighton, back down the prom and bridges again, via Hamilton Square and through the Birkenhead Tunnel.
All the usual stuff is on the site, including a nice video of last years event as the runners go past the local landmarks and interwiews with all the happy runners, plus time lapse and fly-through of the route.
Naturally, it doesn't show the views of the people who were basically trapped in their own streets due to the course design, but you can read about that side of things on Wiki - just search for 'marathon'.
n.b. Their site does include a contact box for your comments.