Whitehorse is a very unique city and those moving there either it love or hate. To love it you need to be open to the tons of recreational activities they offer. You need to like winter though it's a very dry cold and the days are very short.
To get a a "feel" for the place I would suggest you start reading some of the local newspapers because they are a wealth of information.
http://www.yukon-news.com/news/08sep2008/http://www.whatsupyukon.com/http://whitehorsestar.com/archive/news/ They will tell you about what is happening in the city itself, read about cultural events, sporting events, etc. They will also have a calendar of events so you can see what the city has to offer. Newspapers are also a good source for seeing what is available in the rental market.
Another website which is a must is the one for the City of Whitehorse. There you will find everything from "off leash" areas for your dog to the transit schedule
http://www.city.whitehorse.yk.ca/ Here is the city guide to services where you will find community groups, health and support, festivals, churches, service and social clubs - almost everything you need to know to get the feel of the city.
Here is your Total Business Directory: Almost any restaurant, grocery store, dentist, bar, etc is listed here along with a map.
http://www.canpages.ca/business/YT/whitehorse/6158-directory.html Check here for the Extra Foods flyer to compare grocery prices:
http://www.smartflyercanada.com/flyers.html Now to get to the important stuff like living accommodations. Apartments are definitely at a premium and premium prices.Here are a few building to call and find out what the availability and prices are like.
Christina Apartments (867) 668-2741 1C-502 Lambert Street
Hobah Apartments (867) 668-2005 1 Teslin Road, Whitehorse
Yukon Apartments (867) 667-4076 201-28 Lewes Boulevard,
Skyline Apartments (867) 667-6958 37 Lewes Boulevard, Whitehorse
Since you will be working in a government job it should be easy for you to connect with some of your new co-workers well in advance and ask them about rentals. It may be that someone within your new department will know of an apartment. Co-workers are usually a pretty reliable source of information especially in the northern communities. You should ask them if there is something important you should be bringing with you that may not be available in Whitehorse.
I will say though that you may have to revisit your budget to see if you can find some more cash to put towards that new apartment.
Hopefully these will be of help to you.
Good Luck