I have been repeatedly getting less than 20 mpg on my 2003 I-4 Camry. Most of my driving is in the city but still 19-20 mpg almost always seems very low. Do you guys have any suggestions?

19-20 mpg isn't all that far off it's 23 mpg rating. Have you been doing all the normal maintenance when required? Have you checked your tire pressures lately? You could get the static timing checked. Retarded timing can cut your mileage down a bit. Have someone else drive the car for a few days and see what mileage they get.

Have someone look at your brakes. You may have a dragging brake pad/shoe. Check your air filter - see if it's in need of replacement. Do you drive it fairly aggressively?

I have done all the regular maintenance and I usually dont drive too aggressively. I will check to see if the air filter needs replacement but I only have 22,000 miles on it so I doubt it needs replacement.

22k may be alot of miles for an air-filter, depending on the dust/polen/dirt content of the air where you live - and other things.