I recently hit level 5 on my stalker and decided ide like to make a nightshade. After visiting the stalker trainer in Mag Mell, I am prompted with a question asking me if I would like to be a [Ranger] or a [Nightshade] . This shows up as a link and they have been working for me on all NPCS all throughout my first 5 levels doing lots of random little quests.

However, when i click on [Ranger] I am told "I don't know something about this class" from the trainer. When I attempt to click on [Nightshade] I am not given any text, its as if I never clicked it at all!

I have also tried visiting various different trainers in the area, including the ranger and nightshade trainers in mag mell / tir na nog. The specialty trainers tell me that I must seek elsewhere for my training.

I am POSITIVE that I created a stalker, so please don't offer that suggestion. I have already used the Stalker trainer several times.

I am completely out of ideas; is this a known issue or is it just a bug for me?? anyone please help!!

You need to go to the nightshade Trainer to become a nightshade.
The stalker trainer will not "promote" you to any class.
(Note: Shars can't be nightshade)

ya i went to several different nightshade trainers... and they tell me that I need to see someone else for my training. I am stuck.

What race is your toon?
Shars, lurikeens, celts and elfs can be stalkers, but only lurikeens and elfs can become nightshades.

The one in Mag Mell is behind the building with the guardian etc trainer, try him if you haven't already.