In version 7b (the most common base download), Pokémon and #385 (Jirachi) are listed in the National Dex but are literally unobtainable without cheats. Do not waste time hunting them. Later patches (like Blazed Glazed 1.3) fix this by placing them in the Mystery Garden.
Some Unova Pokémon can be encountered:
Certain Pokémon have no in-game hints:
The Pokédex is split across three distinct geographical areas. Each offers unique encounters that are essential for a 100% completion list: pokemon glazed pokedex list work