Well, I've thought that it may be useful for somebody who hasn't traveled between Russian towns and cities before or who wants to travel alone. Well, fortunately nowadays it's as easy as to travel around Europe, you can buy\book tickets on internet. With hotels it's a little bit more difficult, but I think not a problem either.
So, let's start with airplanes.
There is one airport in Kirov's province and it's not far from Kirov. It even has its own web-site: http://www.pobedilovo.com/ but only in Russian, however Google Translate is always at your service. If we can trust the information given on the web-site, you can come to Kirov from the following cities: Moscow (Vnukovo airport), Naryan-Mar, Perm, Izhevsk, Ufa, Kazan, Samara. There are also transfer flights: Orenburg <-> Kazan, Kazan <-> Penza, Saransk <-> Kazan, Saratov <-> Kazan.
I suppose flights from Moscow are the most interesting for foreign travelers. Frankly speaking I found ticket purchase system and a good working timetables only on UTair web-site (http://www.utair.ru/en/index.html). But it's also possible to buy ticket with the help of "intermediary companies", for example http://www.davs.com/services/airtickets/ .
For those who speaks and understands Russian the site http://avia.tutu.ru maybe useful.
From the airport to Kirov you can get by bus #116. The trip takes approximately 45 minutes.