I would like to create a ranged damage dealer. Which class should I pick?

So, I heard you like doing damage at a distance?

Currently, the three best classes for ranged damage using weapons are rangers, rogues and artificers. There are advantages to each and you should pick the one that better suits your play style. However, you have to buy the artificer from the DDO Store or earn it from House Cannith Favor if you don't have it already.

Artificer
The artificer is a versatile class that combines ranged weapons and a companion with spells to create a potent damage dealer. The artificer can also disable traps. The artificers weapon of choice is the crossbow. There are several types of crossbows, but the most favored types are heavy repeaters and light repeaters. If you can find a heavy and light repeating crossbow that are the same, the best choice is the heavy as it does more damage. The artificer can also get them an ability where you can shoot endlessly for six seconds.

The next bonus of artificers is their spells. The artificers have repair spells, so you can heal yourself if you are warforged or take the feat Construct Essence, which makes you part construct but still allows you to get some healing from regular healing spells. You can also heal your pet who is a construct. The artificers also get weapon and armor buff spells, such as Enchant Weapons, which can make you do more damage. Artificers also have access to some of the greatest offensive spells, such as Blade Barrier which can do alot of damage.

Ranger
The next class is ranger. After all the artificer can do, you probably are wondering how the ranger can hold up. The Ranger can hold it's own. Rangers combine healing, self buffing and bow damage to destroy the enemies. But, in addition to that, rangers can dual wield weapons and do some awesome damage. Rangers gain evasion which is a very useful feat that can reduce incoming damage in certain ways.

There are two options for ranger bow damage. The tempest is the melee line but can still do some respectable ranged damage. Since this is about ranged damage, we will talk more about the arcane archer, which has the possibility to have the highest damage in game for 30 seconds every two minutes. This is called manyshot. In addition to that,rangers can use imbues to boost damage. The best one is a slayer imbue, which on a vorpal hit (a 20) can instantly kill or do 100 damage. Combined with manyshot, you will see some BIG numbers. Rangers also gain 5 favored enemies, which (without enhancements) does +10 damage to 5 enemies which is a very big increase.

Rangers can also cast spells. Well its not as robust as the artificer spell book, it has some very useful spells. The ranger has healing spells that are more than enough to keep you up. The ranger also has some useful buff spells that can help you and your party.

Rogue
Now, even though ranger and artificer are much more used than it, the Rogue Mechanic can still pull out some great damage, and so I believe it is worth mentioning. The Mechanic's main weapon is the crossbow, just like the Artificer. The Rogue can disable traps as well. But, in addition to that, the Rogue does something called sneak attack damage. And not just a little, but 10d6 of it. If you are not familiar with D&D dice, that is 10-60 damage. That adds up quickly. The bad thing about sneak attack damage is that it only applies if the monster isn't attacking you, so try to avoid getting them to attack you. Stick em to the melees. Rogues also get evasion like rangers, and can get improved evasion.

Now, although rogues by default don't get to cast spells, they have the ability to use something called UMD to cast spells with scrolls. This essentially allows rogue's to cast any spell in the game with a high enough UMD. But, at high levels you cannot buy the scrolls from vendors, so if you want to use a high level spell you have to buy the scroll on the auction house or find it in chests.

Conclusion
So, as you can see, all choices are respectable in their own right. All three can do awesome damage and have the potential to self heal. But, the most important thing to remember is that this is your character, and you should make sure to make what you enjoy the most.