When we first started this web-site back in the (very) early 1990's we had a large section on postal services in Namibia, including sections dealing with post restant. To be honest I'm not sure there is much need to say anything about postal services today so the only thing I am going to mention is that Namibia has some very pretty stamps and if that sort of thing interests you try and get your hands on some.
Please give me some good advice in your next letter. I promise not to follow it. Edna St. Vincent Millay