I heard that two people are going to run into you and try to kill you and when you defeat them they drop a note.

I have been walking around for HOURS (real life hours, not in-game) and have yet to run into these asshats. It's getting really old and i'm getting to the point where I don't even feel like playing any more. WHAT DO I HAVE TO DO TO START THE QUEST!?

As a side note i'm a level 37 so i have completed the main Skyrim quest. I walked around Skyrim and nothign happened, i got on the boat to Solwhatever and nothing happened. No cultists at all.

Sounds like a bug as all you need do is start windcaller in the main quest and the cultists show up.

The cultests should have attacked you almost immedately as you've already completed the MQ. Typically they'll attack the first time you fast travel to a town after finishing http://www.uesp.net/wiki/Skyrim:The_Way_of_the_Voice. I have no explanation for why that didn't happen. You did travel to towns right? You didn't spend four hours wandering the woods did you.

It is possible to skip the normal introduction.
Go to Solstheim and head to the north eastern end of the island and learn the first word of bend will from http://www.uesp.net/wiki/Dragonborn:Saering%27s_Watch. Then head south to the Wind Stone and use the shout on the stone. Then head to the Skaal Village and speak to the Shaman. Its slightly out of order but workable.

Make sure you go into a gated city. They should greet you at the door when you enter. Make sure your character knows they are the dragon born.

It took me hours to be attacked as well. I was eventually jumped in Frostmoth whilst perusing their excellent wine collection.

I was at level 32, and was at winterhold college When I downloaded both Dawnguard and Dragonborn at the same time. In the main quest I hadn't even gone to Aluddin's Wall yet. The second I walked off the grounds of the college into winterhold the Cultist and the old dude from Dawnguard were coming towards me, and both quests picked up. Though the guards told me about dawnguard after the cultist attacked, and before the old guy could stop and talk to me.

You did download the patch before the DLC? if not you will have to delete the DLC and download it again. Then once it is properly integrated with the main game Dragonborn will start normally.