my babies were fussy too. usually it seemed to be some sort of gassy tummy problem-- colic. one magic trick we had was one of those giant exercise balls-- they loved sitting in our arms and bouncing up and down (really big bounces- not nice gentle soothing bouncing!)
another thing that worked liked a charm was to hold them upright, facing out, with my arm on their tummies... or should i say IN their tummy. i would put a lot of pressure on their little stomachs and it really helped relieve the pain.
one more thing that worked too (hard to describe, but i'll try) was to hold them lying down, face out, with thier necks in the crook of my elbow and my arm on their tummy and holding them between their legs. it also put some gentle pressure on thier tummies and calmed them down right away.
do you have a sling? that works too, and gives you arms to do stuff AND hold the baby at the same time.
also, as someone else mentioned, notice what you're eating before he gets fussy (it's about 4 hours from your mouth to their milk, i think) and WRITE IT DOWN. you may notice some patterns... we had issues with sausage, milk, onions... so pay attention to your diet too.
hang in there, it gets funner! i promise!