If you can get real sudafed (the kind mentioned by lifeliberty) in a non-drowsy formula, that's probably your best bet.
If that doesn't work, DayQuil should be a good fall-back -- it won't make you sleepy during the day, but also shouldn't keep you awake at night. It doesn't do anything for me as a stimulant at any rate. (though at this point caffeine has ZERO effect on me anyway - I could mainline espresso & no-doz cocktails and still sleep like a baby)
Drinking lots of fluids and getting lots of vitamins definitely helps too. If you're not used to getting those things in your diet, then they should have an even faster effect.