TS mentioned "budget constraints"..so how come those 24-70 f/2.8 or 70-200 f/2.8 lens considered for recommendation?
Canon EF 50mm f/1.8 will be not bad IMHO. it can do decent lowlight work and nice portrait shots without having to squeeze out your bank account.
don't forget u guys also reminded him about memory card, tripod, bag, cleaning stuffs, extra batteries, dry cabinet...wow...
what about flash gun and battery grip