Thor's had a variety of costumes over the years. There's the classic Kirby costume, of course, which we have plenty of pics of already, and then...
the Simonson armor:
the Godpack costume:
Deodato's ugly bare-chested costume:
Deodato's uglier S&M costume:
the King Thor armor, drawn by Alan Davis here:
the updated Simonson armor by Andrea DiVito:
and, finally, the new costume, drawn by the late, great Mike Wieringo here: