I’ve seen some good domain names that are expired how to register it agian for me ?

I have a Yahoo!® domain that expired over a month ago ;-((( My “new” registrar says “I need to get an ‘Authorization Code’.”

I need to know these details as i’m having these similar problems with my offical domain name. The service provider says that your domain as it is expired is into some other place i dont know what name he said but the summary is he said its expensive to renew an expired domain. IS IT CORRECT ??

I run a website and when my domain expired it was offline for 2 weeks & now renewed,but when i try my common keywords on google -never gives the home page but only other pages like contact,disclaimer etc.
Where did my homepage gone out ouf google and yahoo indexing?
please help.

I don’t know how to ask this question (wording). But maybe someone has an idea of what I’m talking about. You go to maybe a misspelled domain name or an expired domain name and it’s an annoying search/ad page. What are these pages called?