Check out the custom Wayne thread in the DC Comics custom section. I found a lot of good info there. I recently bought a ZYTOYS black suit off of eBay that was cheap and I like it a lot. I posted pics of it in the thread I mentioned above. Hope that helps.
I have bought EB MIB Jacket and Pants for Wayne. Haven't dressed him up yet as I do not have a good shirt+tie, but hopefully, he will look good. If you are looking for something high-end, you could take a look at Kato's 3 Piece Suit.