Tim Thumb / Image resize issues

Ok, I’ve one really gigantic problem…I need images auto-cropped for the the insane amount of content to come. I’ve looked at tim thumb’s official site, and everyone elses for a month straight and I still don’t know how in the world to use it. They only give these super dumb, vague directions, and it’s pissing me off.

This would be VERY useful:
1. Someone please tell me how to just include it in my present theme so it autocrops when an image is applied, and most importantly….
2. Only needs a relative url, such as: wp-content/uploads/2009…etc because I might be doing a lot of changes.

I know this might be bothersome for some to answer, but I beg of you. My site at finallyanime.com is almost finished, and this is basically the last major thing I need to implement. Thank you and good luck.