My work has brought me to Birmingham as well. Birmingham is not a very busy airport and it gets a lot of FlyBe's. However, it does get some biggies like Emirates, Turkmenistan and PIA. Spotting is limited to two spots if you don't have a set of steps to reach over the high and shielded fence surrounding the perimeter. One is a park, the other is the long-stay car-park. Here some pictures from the car-park, where the sun was already getting difficult, so I didn't stay for long.
Extra long Triple Seven from Emirates:
Helvetic for Swiss:
Monarch is also a frequent flyer:
And in for a quick fuel-stop was this BN-2 from the RAF:
Next stop (and free from work!); Manchester and after that... Heathrow.
Cheers!