Can anyone recommend a book/set of video/exercises to help me onto the next level with c#

Question

Hi

I've been doing c# for about 12 months now - I'm ok with Classes and Methods and creating Forms to a basic level. I've bought about 4 books which seem to cover the basics failry well.

Now I'm in a bit of a rut as I'm still unsure of how uses Interfaces, Delegates, Regular Expression and something called Design Patterns. Someone recommended me a book called Gang of Four to help me learn about Design Patterns but it seems to be out of print.

Also the Microsoft c# Step by Step looks good but I'm not sure about buying it for some reason. Also the C# In Depth looks good but I'm not sure it will go too deep for me.

Can anyone recommend any references to help me onto the next level with c#.

Also please bear in mind that I'm not a Professsional Developer as yet so I am limited to spending 3 or 4 hours a week learning and refining the skills.

Can anyone give me some good ideas where to go from here please.



Cheers

Matt