my .com website is already listed in google.de, and other main country search engines when you search in that area.
So is there any benefit to obtaining the same domain name with different country codes? Do most foreigners use global search preferences, or local preferences? I am trying to find what benefit it gives me to obtain other country codes for my website.
Local domains can be helpful to some search engines and directories for categorizing your site. I know of local search engines which will only return results for specific country domains. However, it all depends on which countries and languages you're targeting. ex. Buying a .jp domain to target the Japan market will not be too effective if you don't have content in Japanese.
As stated by Bill, a local domain extention can boost your ranking on country specific engines.
There as been theories that Google UK gives more importance to a site hosted in the UK and with a .co.uk extention, on top of that, say a user does a search with the parameter "pages from the UK", having a .co.uk extension could probably boost your ranking...