Check the whois. If the domain is Pending Delete, use Pool.com, Snapnames.com, and eNom.com regardless of where the domain is registered. Pending Delete domains actually get released, and one drop catcher doesn't get preference over the others in that situation (except, of course, depending on how good they are at catching... all 3 of the ones listed are pretty good).
You can use my site, AllDrops.com, to determine which catcher to use as well. Pending Deletes are referred to as True Drops (so use the 3 listed above). If it's listed as something else, you will want to use the preferred partner listed to catch it (TuCows, TDNam, Snapnames, Enom). The site is updated daily with the most recent droplists available by all major drop companies.
Good luck!