i like the evilness of the .sk domains, but im unsure of who sells them?

also, what about .jp and all the other county's domains...where can you get those?

Usually direct with www.nic.countrycode e.g. www.nic.sk. To buy them directly from the NIC is the cheapest but also comlicatest way. Be aware that there are countries with restrictions (e.g. you need a local representative).
There are of course many resellers in the US selling also this countrly tlds, e.g. speednames.com or alldomains.com or ....