The World Intellectual Property Organization (WIPO) is a great resource to learn more about patents and trademarks worldwide. This organization manages the Patent Cooperation Treaty (PCT). The PCT is an international agreement by 125 countries around the world. It allows inventors to begin the patent process in many countries at the same time. WIPO also provides information about intellectual property in many countries.
Find the intellectual property office(s) in your country on this list.
The United States Patent and Trademark Office (USPTO) provides basic guides to both patents and trademarks on their website. They will give you an overview of the different types of patents and trademarks in the US, how to apply for them, and what happens after you apply.
You can find a step-by-step tutorial on how to conduct a patent search in the US on the USPTO website.
The USPTO also provides a series of training videos about trademarks if you would like to consider applying for a trademark on the name or logo for your invention.
The USPTO also has Patent and Trademark Resource Centers around the United States. These are libraries that receive official USPTO materials and have specially trained staff who can help you learn more about patents and trademarks. They may be able to help you start your US patent or trademark search.