Thanks guys.
I have promiced not to buy any more guitars, so I can´t spent money on that.
Fran: Like Todd said it´s not excact sience, but you can find alot of information about the subject online, and Auralex provides ideas and basic rules also. The most importand thing is to treat the area around the mixing area. It´s also importand not to use too much foam in the room but then it will sound dead unless you are going for that vibe. some reflection is neccesary to keep the sound alive.
Gary: No other place for the phone in the house, but it´s a old house. I probably get another chair, but this one is not very comfortible and it will be without arms of course, the are annoying when you are playing, but I use the other chair in the room when I play the guitar.
The KRK are very nice and I think you can´t do much better then the Rokit line in that price range. It´s more than enough for home use. I bought Rokit 6 with 6" woofer, and I think it is perfect size for a room like this, but if it were bigger I would have taken the Rokit 8".
KRK has also more expensive monitors the "V" line, but they cost alot more. You can´t go wrong with the Rokit series.....highly recomended.
But to get the best out of any monitor you have to accoustically treat the room in some way.