Welcome to the fandom, Kashi!
Don't worry about not being able to play Door To Phantomile or other Klonoa games right away. If you have a Wii U or can get your hands on one for cheap, you can get quite a few Klonoa games from the Wii U's E-Shop. Other than that there are multiple playthroughs with and without commentary on YouTube that you can watch.
My entry to Klonoa was the Wii game. It goes for a fair price on eBay and is not quite as bad as people say. Just be sure to set the language to "Phantomilian" in the settings menu before you begin. The English voice-acting is very strange.