02 Avalon pulls left, do I need an alignment?

There are several possible causes for a vehicle to pull, in this order of likelihood: 1) improper tire inflation; 2) alignment problem (including damaged or bad steering and suspension parts); 3) brakes dragging on the side the vehicle is pulling towards; 4) tire problem.

If the tires are properly inflated and do not have any bulges, then I'd have the alignment checked.