When I read .NET blogs, I see a lot of links to Eric Gunnerson's C# Compendium or Don Box's Spoutlet or many of the other well-known personalities in the .NETiverse - often the same people are linked to again and again.  But there are a few lesser-known individuals that frequent Microsoft's public newsgroups who's knowledge and .NET-fu are definately up there in the statosphere virtually and of the better-known personalities in and out of Microsoft and you would do well to check out their posts regularly.  Maybe they don't blog, but hey they're too busy answering questions, dammit!

NETMaster aka Thomas Scheidegger is a complete .NET God.  When I first saw his name “NET Master” back in July of 2001 I was convinced no-one without @microsoft.com in his/her email could know enough about .NET at that point to claim the title of 'Master'.  However I was wrong.  Thomas consistantly has some of the smartest answers to technical questions I've ever read, and he does it in (at least) two (human) languages.  Check him out.

Jon Skeet was already an extremely accomplished Java programmer when he came to .NET and he also provides the most intelligent and practical answers you will find to questions about .NET the CLR C# and computer science in general.  Especially nice is the fact that Jon will often give objective comparisons with Java (particularly HotSpot) without a hint of partisanship.  I particularly like his explaination of parameter passing and his insistance that posters give “short but complete programs” to re-create their issues.  Check out his articles on C#/.NET, which he's created to answer command questions people pose on NGs.

Mattias Sjögren.  If there's a question about Reflection.Emit or Runtime.Interop that needs answering Mattias WILL have the answer.  It's uncanny how he can know so much about these areas of the framework and you will often see him answer questions others will not (or more likely cannot) touch. 

Nicholas Paldino is like the de-facto prefect of the C# language newsgroup.  He's given out probably millions of dollars worth of answers on the entire range of C#/.NET questions, helping both the simple language questions to the most complex P/Invoke questions you'll probably ever see.  He's well known to all posters and lurkers (so much so that newbs often mention him by name in their subject lines).

I know there are TONs other people out there MVPs and casual posters alike that have contributed a lot, I just wanted to mention some of my personal favourites here and encourage other to learn from their examples.