Hello i have been trying to level engineering forever but it gets soo boring running all over the place for false information etc..

Can someone please give some decent info here like for example..
once you get to lvl 300 were do you go to choose gnomish or goblin and when you choose were can you go train? and what can you make to lvl it up quick?

If you're considering taking engineering and have yet to do so, stop.  There are so many other professions that far more practical and lucrative.  Even with the addition of epic head gear for all armor wearers and the craftable epic mount, engineering is more pain than pleasure.  Having said that, and as an engineer (goblin) since retail, I'm glad I took it.  I've had fun with it, and I'll hang onto it, mostly because I'm stubborn and because I love making (and using) things that go BOOM.  And lastly, having mining as my gathering profession has been a steady stream of significant income.

Anyway, leveling mining past 300 is a time consuming, expensive proposition, but most professions are at the 300+ level.  The WoW forums have a good guide to leveling engineering to 375.  WoWwiki has links to others.

Choosing goblin vs. gnome is a choice you make early on, I think at about the 225 skill level.  There's a forum here discussing that choice, and the benefits of each.  Basically, goblin engys blow shit up, while gnome engys tweak the world.  Some of the gnome trinkets are pretty kick-ass, however, and can do whopping amounts of damage.  Good luck.

For the post above which advices not to take Engineering, here's a little comment.

For Hunters, Engineering is a fantastic profession in my opinion. When you combine with mining, and probably got your mining skill quickly skilled up, you'll also level your engineering besides very fast. When you're ready for Outland, you should easily got 300 skill of em both.

You can at any time of the engineering career learn to make bombs\grenades, which includes stunning the enemies. This is very good for PVP especially and also when you're having a pain in the ass while questing.

Later, you can make both bullets and arrows, which is extremely good ones to use at lvl 62. In fact, the third best ranged ammunition in the game, and it costs nothing to make as long as you're doing your mining correct.

Also, seaforium charges come in handy when grouping with others than rogues. Always, people ask for rogues to picklock they're boxes, but hey.. ask if someone got enough engineering to do it once! You'll be surprised.

Scopes, increases your dmg\crit.strike rating does always come in handy as a ranged hero :)

Together with seldom recipes as the mana\health -injector, powerful goggles, jumper cables to resurrect partymembers, this IS in fact a very good profession. And with the ability of making flying mounts lately, i'm sure blizzard will announce even cooler things to make this profession more attractive.

Hope this helps a little.
Bulleteye \ Zagharion (Horde @ Laughing Skull).

The one and only reason, for any other class to take this job, is coz you can farm primal airs for money. They drop like RAIN from gass clouds. So you wil be Literarly(sry if spelled uncorect) making money out of AIR. Since no one esle can farm Primal air with such a speed as engineers, and since this job is so owerlooked, you will be a king of the market along side the avarage "Joes" who work hard grinding mobs. You can also create Khorium Destroyes, this is like best gun for all round classes, to replace your old quest or dungen gear, they sell good and they sell expencive.

Flying mount for me is a big load of bull, since the only cost reduction you get is for the mount itself not for the skill. Skill outprices the mount itself by alot: 1 to 10 a normal one and 1 to 25 for epic. + IMHO ITS JUST DISCUSTINGLY LOOKING RESEMBLENCE of a modern day something that i'm not even shure what.

So in most cases this proffecion is only for making money FAST AND EASY(specialy on new servers, like half to one year old) if your someone else then a Hunter.

Where does one go to train above 300? I'm at 296 and have learned all I can from the trainers in Azaroth.