Kazakhstan is a bit out of the ordinary and the visa process may put a lot of people off unless they have a contact or live close to an embassy but I just wanted to add a quick note or two for anyone tempted and also about guides being expensive...
Once you are over there there's an army of people offering help and to act as a taxi or guide for reasonable money, if you trust them or not is another matter but our experiences over there were good and when I asked about the possibility of being abducted or robbed by blokes offering services the answer that came back was that people are too scared of the police to do anything bad...
Another possibility is to go on a Kazakh fishing forum and see if it's possible to join an expedition or book through a UK company doing trips there as I think that does happen.
The main issue with Kazakhstan is possibly the visa process and knowing where to go when you're there. I ended up there because my GF at the time is a Kazakh (although I met her in northern England

) and from a very well to do family so she knew all the best places to go etc. The visa process was a problem for me as I live so far from an embassy but luckily she was from the same tribe as their man in Belgium where my GF was based a lot of the time and he sorted my visa out until he was moved on and posted elsewhere. Other than that my visa was arranged via a Danish company who I was working for as it's easier or at least it was at the time easier to get a visa through a company than to do it as an individual and hundreds of miles from the embassy.
It's an absolutely fantastic place if you're lucky enough to have money and can stomach being exposed to the poverty, a bit like Thailand and other places.