I just moved in the middle of December, the only painful thing we had to do was pay double rent (1/2 month for the new place and 1/2 month for the old place). We are still shocked and amazed we got our new apartment without any "help" as well, money, or friends of cousin's uncle's wives who happen to work in the realty agency.
You're actually in a good place subletting, I'm assuming you don't have to give long notice to leave.
I'd also recommend
www.immostreet.ch, and my realty company
www.gerance-crot.ch (they never show up on those other websites). There is also
www.anibis.ch, a type of craigs list. We listed our apartment there, and it was taken over after 4 days.
The only other advice I have is DON'T WAIT if you see something you like. Sometimes you wait 2-3 days to make a call for a visit, and the apartment can be gone already. Good luck with your search!