Clicking the Stores LOGO's will give you the TP for their respective stores In World.
Although I recommend you go see this there isn't usually a lot there for guys but what are there are good.
I don't advise going on opening day or the day after, it get packed, laggy and sometimes can be impossible to get to with a TP. They do however have a Cam Sim where you just pick a spot and send your Cam across the void.
This is a long established store in Second Life offering a great selection of both New and Old Style fashion
(Yes! There are still some that wont change over to MESH).
One good thing about here is that you can buy complete outfits with a great range too.
Footwear, Accessories, Glasses & Hats. It's a bit on the pricey side but good quality stuff.
This is not a store, this is a Bible.
Everything you want to know about fashion in Second Life you'll find here.
There are lots of links to Events and Stores and it's a great resource for Blogs about fashion here too.
This is everyone's Go To for fashion news in Second life.
I've covered what I think are the best places based on where I have personally bought my clothes from. Obviously I haven't been to every store in SL and there will be others just as good, if not better.
If you think I should add stores please go to look at Cold Ash or Deadwool first and if your store or a store you shop at is as good a quality menswear store as those just let me know. I'll go see and then add here based on my findings.