Have never heard of, nor never used this site before. And upon trying to look at it, it's a 404 not found kinda thing on here.
But if you are serious about buying Bitcoin, alebiet from a different source, your best bet if you don't care for giving up a tad of privacy is going to be something along the lines of Coinbase. Lowest fees on purchases, only downside is that you're going to have to show an ID, Passport, or one of these items.
If you do care for privacy though, you have to pay the piper on LBC or Paxful with an anonymous(ish) payment method.
Good luck and welcome to Bitcoin!
What are you talking about? Did you visit the site mentioned of OP? and do you analyze that OP doesn't want to buy or sell any bitcoin or any other coins?
He even replied before you that he wants to buy a Casascius bitcoin not a Bitcoin dude. If you still don't know what is Casascius then go to google then search about it, here's the link for the help
https://www.google.com.ph/search?q=what+is+Casascius+bitcoin&oq=what+is+Casascius+bitcoin&aqs=chrome..69i57.5365j0j7&sourceid=chrome&ie=UTF-8*Spam posts everywhere
And to OP if you want to sell your Casascius, try to visit the Collectibles section of this forum here
https://bitcointalk.org/index.php?board=217.0,
You can see different topics who want to sell their Casascius too. If you want to proceed to sell make sure that you take pictures of those coins write your name on a piece of paper and the date also to prove that you own those items on hand. Then make a thread and also escrow is a must for the protection of the buyer so you must consider it.