Im a new member and have several books to post that I have already read and several that I have not read yet. I entered all the books that I have not ready anyway...thinking they would automatically go to my TBR file, since I clicked the box that said i had not read yet. But that didnt happen...so where did those books go that I posted...i cant find them on my account. 

It looks like you posted all of the books to your bookshelf. If there are some you aren't ready to swap yet as you haven't read them, you might want to remove those (unless you can read them quickly when requested).

To add books to the TBR, go to "my lists" then find the tab that says TBR. There is a button on there that says "add TBR".

I would remove them quickly before they start getting requested.  If any were WL they will already be offered to the 1st person in line.  If you put your account on vacation it won't any WL books that are about to time out be offered to the next person. So you'll be able to remove them.

If they get requested then you'll have to decide if you can read them by the mail by date or not.  You can deny the request which removes the book from your shelf.  Or you can take the full 5 days to accept, then choose the 5 day mailing option and give yourself 12 days to read the book (you get 2 days after the mail by date to mark it mailed). 

I forgot to check if a thrift store find was WL before I posted it.  It was an romance from the 90's and I actually figured it would sit on my shelf a long time before being requested. But it actually had a short WL. So I just waited an extra day to accept the request and chose the 5 day mailing option.  But that was only 1 fairly short book.