Reduce Temps in Confined Areas

I built my rig right around winter, and at the time the heat produced actually felt somewhat good as we keep the house cooler. Now that its summer, the heat is driving me crazy (Along with the sound of the stock fan-Headphones helped this though   ). Anyways, I cant stand playing games for more than 45 minutes at a time because of the heat expelled from the case. Funny thing is I only have one fan-my intake.

1.) I planned on adding fans to my case, but I realized it wouldn't do much good as my computer cabinet is really confined (Maybe 1.5 inches on each side and 1/2 and inch in the rear which would be a pain in the *ss to remove, the flimsy fake wood stuff). Anyone have any inputs on fans (Don't want to buy 30$ worth of fans and still have the same temps   )?
1a.) Any other cheap ways (20$) to keep the temps down? I plan on a H50 when the H80 and H100 comes out, but as now I cant afford it.

2.) Any ideas to keep the heat from getting to the point of unbearable around the case?

3.) Games lately have been having sudden drops in FPS where it used to be buttery smooth. (Assassins Creed DX10/Mass Effect 2/Crysis DX10) I have watch componant temps almost religiously   and they have always stayed in the upper part of my acceptable range (GPU: 75 C's CPU: 50 C's), and it doesn't artifact.

Kind of alot of questions (Most being commons sense), but I wanted to get peoples opinions, and thought since I was already making a thread might as well ask the last question.  

My Rig:

Windows 7 Home Premium 64 Bit
Cooler Master Elite 430
AMD Athlon II x3 445 (Unlocked to Phenom II x4 B45)
MSI 870-G45
MSI GTX 460 1GB Cyclone OC'ed to (815/2000/1630)
4GB G. Skill DDR3 1600 RAM
500 Watt Corsair PSU

Was planning on a major upgrade in a few months, but the heat is already bad, and add two GTX 570's or ATI 6970's in there and who knows how bad it will be.

Thanks Ahead!