How does backordering a domain name work?

registrar — Tue, 09 Feb 2010 01:32:03 +0000

I entered a domain name to order, and it said it was already in use but that for $18.99 I could backorder it. Is that a yearly fee or one time fee until the name becomes available? Also, should I contact the current owner directly since their registration info is listed publicly and ask if they want to selll it to me? What would be the procedure to do that? Thanks!