toontrader
Axpona really is a great experience, it's audio focused only, and the exhibitor list is a who's who of the speaker world (and integrated amps). You will get months if not years research done in a couple of days.....make sure to be there at least 2 days. I live 30 minutes away, so easy for me to say. Another thing of note, is that many manufacturers and dealers will offer discounts on equipment bought at the show.
Alta Audio, ATC, Linkwitz, B&W, DeVore, Dutch & Dutch, Magico, Martin Logan, Vandersteen, Magnapan, Dynaudio, Estelon, Focal, Fyne Audio, Franco Serblin, Joseph Audio, Legacy, MBL, Rockport, Revel, Pure Audio Project, ProAc, Perlisten, Monitor, TAD, Volti, Yamaha, Wilson Benesch, Vivid......whew. There is not a single speaker manufacturer that I am looking at that will not be there, except maybe Sonus Faber; and they may very well be in a dealer booth
I personally will be spending my time with Volti, Joseph Audio, Yamaha, Pure Audio Project, Fyne, Vivid, Linkwitz, Revel, Franco Serblin, and maybe others if I have time......I'll be there Saturday and Sunday this year.
Best of luck, and hope you can make it