I drink a sweatened tea it has no calories but could it be bad to drink something that is artificially flavored when trying to lose weight?

Yes. I would suggest water... best diet drink in the world!!

Juries still out in this one. Artficial sweetners as you say have no calories so in themselves aren't going to make you gain weight however I have heard some thories that they can mess up your metabolism/ confuse your body.

Against aspartame (the main sweetener in most diet drinks)
Study: Artificial sweetener may disrupt body's ability to count calories (http://www.purdue.edu/UNS/html4ever/2004/040629.Swithers.research.html)
Aspartame: What You Don't Know Can Hurt You (http://www.mercola.com/article/aspartame/weight_gain_myth.htm)

For aspartame
Aspartame Information Center - Aspartame Myths and Urban Legends (http://www.aspartame.org/aspartame_myths.html)
Calorie Control Council | Low-Calorie Sweetener Benefits Q & A (http://www.caloriecontrol.org/lcbenqa.html)

This is definitely a for every expert there is an equal and opposite expert situation.

I am a biochemist but I don't know where I stand on this debate. Both sides have compelling and reasonable arguments. Only time will tell I think. The point here is do you want to be the guinea pig? Everything is fine in moderation, I myself consume sweetners but mainly due to laziness - they are getting very hard to avoid!

You should have a look at these web pages and then do what you want. Your guess is as good as mine.

Here's a tip about sources and research articles - always check who funded it? Do they have ulterior motives i.e. selling a diet drink?