I would like to know something about the traditional finnish knitting patterns, how do they look like etc. Thank you very much

In the address http://www.tkukoulu.fi/handmade/neulonta/perinn1.html you'll find three examples of Finnish traditional sweaters. Especially Jussin paita and Revontulipusero (Northern lights sweater) are very popular in Finland. Jussinpaita was designed according to a medieval pattern. The original colours are burgundy and grey, but also blue and grey are popular. Revontulipusero is of Swedish origin, but became popular in Finland in 1950's and is regarded as a traditional design.

In the address
http://www.tkukoulu.fi/~ausipola/index.htm you'll find more pictures of traditonal patterns.

In a book, called "Kalevalaneuleet" by Marja Ulvo & Elise Rajamäki, 2001, ISBN 951-20-5834-0 you'll find pictures and instructions of knitwear with traditional patterns but designed for modern taste. Unfortunately the text is in Finnish but the pictures are very clear.

Mary Olki has written many books on Finnish knitwear, especially on socks and mittens. Her books date back to 1940's are show the traditional patterns. Her book "Kirjokintaista kauneimmat ja muita neuletöitä", ISBN 951-0-02780-4 is a classic.

There is also a book called "Sydämenlämmittäjä ja tikkuripaita", by Mirja Almay, 1993, ISBN 951-31-0089-8, which shows traditional knitwear both from Finland and Estonia. The book has a summary in English.

And of course there are magazines specializing in handicraft: "Kauneimmat käsityöt", "Novita", which may show traditional patterns as well.