If you need to find a state, in the overview lists of West/Central/East, each state has a magnifying glass. Double-click on it to go to that state. Or, click on the news pop-ups on the left.
Ingenius levels but far too time consuming in my opinion. Then again, there's the disclaimer. =P And Erki, for starters, you can find secret levels by moving your character over top of them.
What worked for me for hard badge (as well as for Deadeye Plat, Kills Plat, and $$): only upgrade your main turret and let the other ones die off. Then just play strategically. (1) hit only that which is coming for your turret; (2) be economic with your ammo: e.g. in the later parts of the level try to hit multiple missiles in one shot; (3) lead your aim @ the green satellites as soon as they enter the screen, shoot, then refocus onto your main turret; (4) only get the "white balloons" when they are a danger to you or when missiles that are coming for your base are passing by (their big explosion will take out those missiles). That's really all. Good luck.
Tip that worked for me: kill the guy (top right), and then focus on the bottom bunk, cause if the nukes come out, you're screwed (I know I was... probably over 10 tries until I learned my lesson).
Made me a bit dizzy, this one. Anyway, I found the key is to control speed via crates. Not too fast so that you can react to windows/things dropping, and not too slow so that you can't make jumps/escape crumbling buildings. For windows, the high ones are easy, the low ones you don't even have to jump. If you go at a good pace, you'll have enough time to stop yourself from pressing the jump button. Let your guy crash through the lower ones. Oh, and never hit more than 1 crate at a time. Got over 10k.
Best Weapon for Crowds: Lightning.
Best Weapon for Deterring Clusters (especially useful for level 58, where Lightning may not be enough): BFG.
Effective Weapon Combination for Final Boss:
-4 Homings
-Energy
-Laser Lock
5/5.
This game was a lot of fun. I thought it was great not having the guide always tell you where to go. I had fun paying attention where I was going and how everything tied together. This made the game more enjoyable, I think. The final boss just needs patience, and it was a satisfying finish, though I wish there was a little more to the story, especially toward the end: I felt lost.
 "Gravitee"){kind=icon}
 "Meat Boy (map pack)"){kind=icon}
 "Closure"){kind=icon}
 "intrusion"){kind=icon}
 "Pandemic: American Swine"){kind=icon}
 "The Tickler"){kind=icon}
 "MoneySeize"){kind=icon}
 "MAD: Mutually Assured Destruction"){kind=icon}
 "Epic Battle Fantasy 2"){kind=icon}
 "Cube Colossus"){kind=icon}
 "Canabalt"){kind=icon}
 "Gravitee 2"){kind=icon}
 "Heavy Weapons"){kind=icon}
 "William and Sly"){kind=icon}
 "Pwong 2"){kind=icon}
 "Run Elephant Run"){kind=icon}
 "Castlewars"){kind=icon}
 "Starcom"){kind=icon}
 "Toss the Turtle"){kind=icon}