This is an FAQ ...
For those with Windows forms apps and moving to WPF apps.. reuse of existing windows forms localized strings is a must in order to save time & money..
Mike henderlight gives you the recipe step by step http://blogs.msdn.com/mhendersblog/archive/2006/03/30/565040.aspx
[while there check all the other posts on crossbow.. It is amazing to me why there is little noise around crossbow.. Is i that it works and nobody needs help, or is it that nobody cares.. Either way you should let Mike know ..