Picture at bottom.
Well, as usual, you will first fight fairly weak pokemon. These are the wild pokemon you will meet in the grass on routes 1 to 5 and possibly beyond.
Yorterrie (#506)
The first one is Yorterrie, the puppy pokemon. It looks like a yorkie. It is a normal type and evolves at levels 16 and 32. An important move that it learns is Bite. This is a dark type attack, which means it is very good against psychic and ghost pokemon. Surprisingly, you will meet a couple of psychic pokemon early in the game.
Minezumi (#504)
The next one you will meet is Minezumi, it looks like a chipmunk. It evolves at level 20. This one also learns bite. Another important move that this guy learns is Bide. Bide takes two or three turns of inaction and deals double the received damage to the enemy. If the pokemon using it survives these turns, it will usually beat the opponent with a single hit.
Minezumi and Yorterre are both normal types, and are thus immune to ghost and weak to fighting. At this point you won't be meeting any of those, though.
Choroneko (#509)
Next you will meet Choroneko. It looks like a purple cat. This one is dark-type. It is unaffected by psychic, which is great, because you will soon meet psychics. It is also resistant against dark and ghost. Its weaknesses are bug and fighting. It evolves at level 20. Of not is that it learns the attack Assist at level 6.
Mamepato (#519)
You will also meet Mamepato. It looks like a regular pigeon. It is normal and flying. Its weak to electric, ice, and rock. It is however resistant against bug and grass. It is also unaffected by ghost and ground. Evolves at levels 21 and 32.
These pokemon are all relatively common and weak. So, lets go onwards to the more interesting ones.
Munna (#517)
The first one you will see is Munna. It is a psychic pokemon and looks like a flying pink pillow. It is weak to bug, dark, and ghost. It is resistant to fighting and psychic. It evolves into Musharna (#518), via a moon stone. At level 7 it learns yawn, one of my favorite moves. At level 11 it learns psybeam, which is a fairly powerful psychic attack, for such a low-level pokemon. Be careful, though, a bite uses its weakness and can do some pretty bad damage to it!
These are the pokemon you will see in your first few days of adventuring. I'll make another post right now for the days 3-5 (if you play at my pace, that is).
The Pokemon mentioned in the article.