- I would make the rounding of your tabs a bit more rounder, they kind of look blocky - for the top area, I would fill all of the white area with a light grey color so it stands apart from the white content area.
You've got a lot of ads! Also I noticed that all prices have the '$' sign AFTER the price. You should swap them around to make it easier to read.
Way to many ads for my liking. You might find you get more clicks from taking some ads away because so many people now know what adsense is, and they know those are just ads. Intergrate them a little better bud