Energy Usage, Conservation and Weather Stripping - Extra Thick Weather Stripping?

I am trying to weather strip the door going to the outside in my garage. The gap between the frame and door is so large, that none of the weather stripping that I've found will properly seal the door. The largest I've found is 5/16" that is good quality (not the foam stuff that falls apart in no time). I've looked at Home Depot and Lowe's.

Does anyone know of some good quality weather stripping that is larger, or would it be worth the time for me to rebuild the door frame to make it closer to the door? We are having lots of spiders (including black widows) get into the garage and I'd like to seal everything off.

See the other post. Now that you explained it a bit more.....

This is what you need to use.....

http://www.homedepot.com/webapp/wcs/stores/servlet/Search?keyword=garage+door+stop&langId=-1&storeId=10051&catalogId=10053

You pull the old stop (if there) off and install this instead. Or put it on top of the existing if its wide enuf and looks ok.

EDIT:
Oh crapola...are you talking about the rollup door, or a regular door???

In this post, I'm referring to the regular door, not the 'roll up' door.

Is the door wood or metal? Is it an exterior door with the metal threshold at the bottom? Inswing or outswing? Did it originally have w-strip installed into a kerf cut into the frame of the door?

The metal and rubber bulb nail on or screw on type might be a viable option. That should cover up to the gap you mentioned.