Quote from another post I did earlier today:
I'd go to the registar's site and see if they aren't offering it as a sale somewhere on their site.If a domain expires it's a free for everyone again. Whoever registers it the first again will get it and that doesn't mean it will be you.
Also a registar isn't required to instantly release an expired domain, some will keep a hold on it for as long as three months and possible offer it for sale to others as well.
Good luck grabbing it