this last level is pissing me off, and i was wondering if anyone who has beaten it has some tips.

Yes they do, and there's a topic just for that. Here: http://www.warlight.net/Forum/Thread.aspx?ThreadID=136

It's still from the old times when it was called Challenge #2.

I posted on the other forum, but I will do the same here. Challenge 2, (Or three, or the 6th level) is designed to make you die inside. That being said, it is beatable. Not easily, as I have never done it, but it is beatable. I am playing it right now with 72 income on the 15th turn, and I am relatively secure. I have 4 enemies on my ass, out of five. A lot of the level is getting lucky with the AI's expanding into eachother and fighting like drunken monkeys. My strategy is this: Deploy all to India on first turn, and attack left with 6 and East with five. Also, attach Central america from Cuba, and Chad with everything from Nigeria. Do this until you come out with 7 in Central America, nothing below 4 in either of the two Indian territories you attacked, and 5 in Chad. Now, you hope that you can take Central America and India this turn, also attacking Tadschikistan.Now, attack Iran, Eastern Kazakhstan, Hong Kong, and anywhere to West US. Now, you should be able to take Caucasus, and expand into Svalbard S, and Svalbard N, also later to Canada N, and Anadyr N. I also tried a new thing this time, rushing Argentina N to get into their Canada. This may not work as well as others, but it is the best I've found so far. Also, if a stack gets too far inside you, surrender and try again, it's only a matter of time.

Definitely on track to win. Unless they pop a random 500 somehwhere, and I forget how to use an abandon, I've won.

And, in 43 turns (Could've done better if I were less careful) it has been won.

Check out the "Challenge 2" thread in this forum, Impaller has a great method description (although beating it once was enough for me, and used a different approach). As le grande sandwich noted, it's all about getting a good configuration of AI nonsense.