What is the best tool or set of tools to perform trademark clearance searches of designs and design elements for products/apparel?

I can help with registering your brand with Amazon. Contact me if you would like to talk.

Hi: The US Patent and Trademark Office has some great resources, including solid search functionality which lives at: https://www.uspto.gov/trademarks-application-process/search-trademark-database Kerby

The answer is: as soon as possible. Trademarks can take 1-2 years before you go through the entire process. You can apply for a trademark yourself on the USTPO site. Might help to have a lawyer or paralegal help you if you are inexperienced. A simple filing costs a few hundred in fees depending on the nature of the filing. (not legal advice).

Yes. That is the whole purpose of the USPTO filing system. Whoever is first to file gets the mark. There is common law usage which they could argue but first to file is generally upheld.

Having worked in the domain name industry since 2001, I would always suggest a trademark search before acquiring names. Please keep in mind that when registering a name, you agree to the Uniform Domain-Name Dispute-Resolution Policy (UDRP) as part of your registration contract. This means that you agree not to infringe on rights of others with the registration of your domain. When selling a domain name, it really comes down to your contract/agreement with the buyer. Depending on the details you might be held liable for any potential trademark infringements at a later time. DIsclaimer: I am not a lawyer, it would be best to consult with a lawyer.