So, I'm moving to Amdsterdam in mid-September, for at least two years, for a post-doc position. I'm not benefiting from any housing arrangement (temporary or otherwise), so I'm looking for a place to rent. 
Now, different people have suggested different avenues for looking for accommodation, among which being the websites kamernet.nl and ikwilhuren.nu . The thing is, both require a steep registration fee. I'm used to these kinds of websites being free, or ad-based; and while I wouldn't mind paying a few EURs to register, these sites that you cough up over 30 EUR (!)
- Is it worth it to register at one or two of these websites? - Are these important means of finding a place to stay, in your experience/opinion?
Thanks, Eyal (who's already busy packing up his stuff.)
 - Well, technically I'm looking for 3 things, which is a place to stay for a couple of days when I arrive; a short-term rental for something like a month which I can commit to before coming over; and a longer-term rental, which I won't commit to until I see the place after I've arrived.