In order to register any domain, you must provide certain personal information that you may not wish to be publically searchable in the Whois database. Signing up for WhoisGuard is a great way to keep your registration data private. WhoisGuard acts as a "shield" for your searchable information, displaying the address, phone number, and email of the domain registrar (Namecheap, e.g.) instead of your own. Keep in mind that WhoisGuard is an optional security add-on that must be renewed separately when you renew your domain.
If your purpose in buying a trademarked term as a domain name is to try to confuse people, you’re opening yourself up to having a complaint filed against you and having to give up the domain name. Even if you’re not trying to create confusion, you’re likely to face some legal challenges by buying trademarked terms in your domain name. To be safe, you can search for U.S. trademarks at www.uspto.gov and make sure no one owns a trademark on the name you are considering.