I've actually just written a book called 'How to Get to the North Pole'
so may be able to help.
The first thing to note is that there are several different north poles.
The one most commonly referred to is the Geographic North Pole
but if you consider the Magnetic North Pole as a viable alternative then that opens up a couple of other options.
The North Pole Marathon doesn't actually take place -at- the north pole - it is run at the temporary Barneo station nearby - but a helicopter flight to the pole is included in the package.
bchetty's recommendation of flying to Longyearbyen in Svalbard and booking a flight north is probably the most economical option, though very similar in cost to the marathon.
'
Last Degree' trips in which you ski the final ~65 miles to the North Pole are likely the cheapest way to reach the pole under your own steam; earning your visit a little more than just being dropped off.
For a similar cost, you can get a longer expedition to the Magnetic North Pole, in one of the organised races such as The Polar Challenge or North Pole Race.
Finally, the cheapest method of -seeing-
the North Pole would be to book a pleasure flight over the top for a view from the window.
Not the same thing as actually going there
but if your priority is low cost then this could be a compromise.
P.S.
There's a free overview of my book available on my website which has more information if it's useful: http://thenextchallenge.org/2010/11/how-to-north-pole/
travel.stackexchange.com/users/6432/Tim Moss
An other alternative is to fly to Longyearbyen in Svalbard and then use the chopper service to visit North pole from around 15000 Euros.
This is cheaper than the cruise trip.
travel.stackexchange.com/users/1441/bchetty
There are some companies that offer trips to the north pole on ice breakers.
They're not very economical, though.
Here's one of several that came up on Google: Quark Expeditions
The 2013 trip takes about two weeks and costs €29,600 EUR not counting your expenses to get to Helsinki and get home again from Helsinki afterwards.
travel.stackexchange.com/users/738/xpda
Some companies offer trips to the North pole.
For example Hauser Exkursionen.
This is a well established company that offers all kind of excursions from the north pole, to the Mount Everest or a desert.
Unfortunately the information is in German, but I think it is possible to understand a little bit of it.
Hauser Exkursionen
However, as you can see, it is very pricey.
For a 16 days trip you pay ~31 000 Euros.
Usually the excursions take place in April as VMAtm already said, so the next possibility will be on April 2012.
travel.stackexchange.com/users/693/RoflcoptrException
I can't say for sure about the prices, as all the touristic expeditions are made in April - the safest time to travel there, and currently all the companies can't say anything about prices (you know, crisis, and so on).
The best option (according to the website quality and feedback from tourists) for you is Polar Expeditions Ltd., London, UK , but still can't find any info about prices.
Other variant, The North Pole Adventures , is a partnership between Russian and American companies.
travel.stackexchange.com/users/19/VMAtm
A trip to the North Pole will not be "economical," BY DEFINITION.
Hence, you might have a hard time finding one that meets your needs.
That's only partly because going there is inherently expensive.
In most "civilized" parts of the world, there is the potential for cheap "deals," because the "full cost" has already been paid by someone ELSE.
That is, a home owner in some city might allow you to use an empty guest room for "free" (or a nominal amount) because the rest of the family has already paid for the house.
A restaurant might have free or cheap leftovers for people, because its regular clientele has paid for their food, etc.
"Cheap" public transportation (and other amenities such as museums) are state-subsidized.
At, and on the way to the North Pole, there are NO other "natural" users to share these costs, so the handful of users (as a group) have to bear the full costs on their own.
The marathoners may get a "deal" from companies who want to sponsor them.
But they are basically in the position of paying for the trip to the North Pole by "working" their way.
Unless you can offer some kind of "endorsement," scientific, or other value for your trip there, it's unlikely that anyone would be interested in helping you defray your costs.
How does one get to the North Pole?
If you have $50,000 to go solo (or even $10,000 to go in a group) to spend on guides, transportation, etc., plus food, fuel, and other supplies for all of the above, be my guest.
But that doesn't seem to be your situation.
travel.stackexchange.com/users/788/Tom Au
I'm aware that annually there's a  North Pole marathon , and that would be one way of getting up there, if exhausting.  What other options exist to get there, preferably economically (the marathon costs are mildly frightening and extremely prohibitive without sponsorship -  €11,900 ).   PROVISIONAL SCHEDULE FOR 2012  April 5 Arrive at Spitsbergen (Norway)April 6 Fly to North Pole Camp & 90NApril 7 North Pole MarathonApril 8 Return to Spitsbergen (Norway)April 9 Return to Homeland
How can I travel to the North Pole, cheaply?
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<adventure><extreme-tourism><remote-locations><arctic>
travel.stackexchange.com/questions/2176
travel.stackexchange.com/users/101/Mark Mayo
A trip to the North Pole will not be "economical," BY DEFINITION. However, you can take the helicopter service from Longyearbyen in Svalbard for around 15,000 euros, travel on an ice breaker or go with Last Degree trips, where you ski the last 65 miles to the North Pole. The best option (according to the website quality and feedback from tourists) for you is  Polar Expeditions Ltd., London, UK. Some companies offer trips to the North Pole, however, none of these trips is economical. Prices, where available, are expensive. 
Some companies offer trips to the North Pole, however, none of these trips is economical. Prices, where available, are expensive. 