Question about OverDrive

Hey guys,
Si
So I just signed up for OverDrive today, and I've found my library with no struggle and used my library card to sign in.
However, I have two questions about this app.
1) Checking out books:
When I hit borrow on one of the books I wanted, I didn't see it in my bookshelf. Do I have to do something before it can appear there?
2) Nice to see the eBooks, but where are the audiobooks:
I can't seem to find any audiobook, even if the app says audiobook in the title, does it have to do with what library I'm using? Because the library I use offers audiobooks, but I can't seem to find any....
Thanks in advance.