you can use arteam toturials !
tutorials section :
Code:
hxxp://arteam.accessroot.com/tutorials.html
and tutorials about .net reversing :
Code:
Tutorial: DotNET Reverse Engineering Episode 1
link: http://arteam.accessroot.com/tutorials.html?fid=191
Tutorial: DotNET Reverse Engineering Episode 2
link: http://arteam.accessroot.com/tutorials.html?fid=192
Tutorial: Primer On Reversing .NET Applications
link: http://arteam.accessroot.com/tutorials.html?fid=187