A few questions about Middle Earth (knights, titles and names)

Good day to you all. I am new to this message board, and have a few questions I hope to have answered.

1. Is being a "Knight of Gondor" a very prestigious title, or are all soldiers of Gondor referred to as knights? Also, if it is a prestigious title, are there knighting ceremonies for those entering knighthood?

2. Are all the titles of nobility we use in our world also used in Middle Earth? I've heard of kings, princes and earls, but are there dukes, counts, barons, or even sirs? Do you earn the title "sir" when becoming a Knight of Gondor?

3. Would the character names "Albrecht" or "Adhemar" fit into Middle Earth? Could they be names of Rohirrim or Gondoran (sp?) characters?

That would be all. Thank you. :-)