new link

http://www.forum.nokia.com/I_Want_To/Develop_Mobile_Applications/

http://www.forum.nokia.com/info/sw.nokia.com/id/dbb8841d-832c-43a6-be13-f78119a2b4cb.html

http://www.forum.nokia.com/info/sw.nokia.com/id/ec866fab-4b76-49f6-b5a5-af0631419e9c/S60_All_in_One_SDKs.html

check these links. There is a lot of information about each mobile's characteristics. for example 5800xm. There also some recommended program to use.