Hi Nado. I travelled in Iceland for a month in 2012. I managed to do some fly fishing there. I think I can answer a few of your questions...
Iceland differs from Canada in that there is no overall license. All rivers are private (and stewarded by the local farmers that have been there for 100s of years). this is why each beat is so expensive.. and also why they are so productive.
At the time it was usually around $400 a day to be one of 3 rods allowed on a large section of any river, guided or unguided. the best Salmon rivers run the most, but the prices seem to differ across Rivers. You usually have to pay the "fishing club" for the day and then you can fish the designated beat. I could not afford it.. but found other ways to fish.
There was a deal on when I was there (it should still be around) - $50 for a license that allows you to fish 50 lakes in Iceland. You can buy the license at most gas stations. They provide a booklet that shows you the lakes and what's in them, plus you do a little research on your own. I found one lake that was brackish water and caught some decent Arctic Char and lost one giant one on a dry fly that still haunts me today (I can try and look it up). I also fished the Varma ("warm") River that is only 1 hr. east of Reykjavik for big resident and sea run browns. It cost 80$ for the permit for the day (sunup to sundown). hooked and lost a couple, but you could see them in there. Upstream or Czech nymphing was the recommend presentation in most resident River I heard about. I have a contact for you there to pay for a day permit to fish that River (at the bottom of post). The biggest lake in Iceland (Thingvallavatn Lake) is home to some of the largest browns I have ever heard of.. mostly caught fly fishing from shore. Last tidbit, Iceland is a midge fishery, so best to get flies there that are local and appropriate. There is a fly shop in downtown Reykjavik. I also suggest you stay at the University dorms, which are turned into a tourist "hostel" in the summer. cheap, good rooms, good food.
As for bringing your own gear, yes it all has to be disinfected at the airport. If I remember correctly it cost at least 60-80USD. It sucks and there is no way around it. I suggest buying your flies there, or tying them there.
Contact for Varma R. Permit
Name: Odinn
Email:
[email protected]
http://fishingiceland.com/
FI.ehf
ID.NR.660907-1730
Baugakór 15
203 Kópavogur
Iceland
Good Luck! let me know if you need any other advice.