It crossed my mind as well, so I've just checked the rankings. The country's two top players are Mikhail Kukushkin (#124) and Andrey Golubev (#139). Golubev is also ranked #168 in doubles
A look at their wikipedia gives the following information -
The Kazakhstan Davis Cup team represents Kazakhstan in Davis Cup tennis competition and are governed by the Kazakhstan Tennis Federation. In 2011, Kazakhstan competed in the World Group for the first time after they won against Switzerland in the 2010 World Group Play-offs. After the first round win against the Czech Republic in 2011, Kazakhstan secured their spot in the World Group for the 2012 Davis Cup. They lost in the first round to Spain, but defeated Uzbekistan in the play-offs, which again kept them in the World Group for 2013. In 2013, they defeated Austria in the first round, but lost to the Czech Republic in the quarterfinals.
Kukushkin's the guy Andy lost a set to at the Brisbane tournament last year, very good player with some huge strokes.