Hi Beth, and thanks for your help!
The cowboy photo is taken at something called "Bud´s Gin Mill" and it´s a postcard but there is nothing written on the back so I guess he must have sent it in an envelope.
There is a return adress, but it is a c/o adress to United American Line, 39 Broadway, New York. So I can´t know for certain that he actually lived there.
My grandmother (it´s her uncle) has the letters but I think the postmarks were unreadable. It´s only three letters I think and as far as can remember they were dated early or mid 1920´s.
I don´t know if he ever married, but he mentions a German woman called Cleary or Clerey Wagner who he might have been engaged to. For some reason he writes down her adress (Langestrasse 36, Bremerhaven, Germany). Probably so he could pick up letters when he came there with his ship. I guess this could mean that he ended up in Germany but since he talked about staying in Los Angeles, I believe that´s what he did.
I will call my grandmother tomorrow to ask her about the postmarks and dates.