well i know how to weld and bend tubing with my trusty tube bender but what type of bit or tool do you use to cut the fisheyes in the ends of the tubes that go perpendicular to other tubes?

Well the right way to do it looks some thing like a lathe that has a bit = in dia to the size of the other tube you want to weld it to.
You turn it on and have a vice that you clamp the peice you want to cut in and then you turn a handle push the piece of tube into the cutter. It is very quick simple and perfect but not cheap.
If you can't get one of those, try a hole saw or maybe a plasma cutter and grinder.

I did all mine with a 4" disk grinder. Took longer but still easier than a tubing notcher.

Best tool for notching/fish mouthing is a notcher, a simple, quick and very fast method used in many mud packer chasis shops. It's simply a lever with a round die that have compound leverage. You slide in your tubing till it hits the stop, pull down the lever, boom your done, all of 3 seconds to cut a fishmouth, flip it over and do the same.

Cheapest/easiest for normal mere mortals working in their garage would be the drill press specials you can get all day long in speed catalogs/ebay that use a 1/2" drill and hole say. I used one installing my cage and iut was nice, but I admit to relying on the 4" grinder for ultimate joint fine tuning.

The mill would be awesome, but how many guys can afford that type of machinery to make it practical?

i just used an air die-grinder for my cage and if i would have had the proper lathes or a carbide notcher I could have done the cage in a few hours less, but for an extra 3 hours of my time it wasn't worth the expense for a one time deal.

well i have a industrial type drill press and i am looking for a bit that i could notch with maybe im on the wrong track

take it to your local jc since i was enrolled i got to use their fisheye machine but it still wasnt big enuff so i had to plasma cut the rest and then grind away