A general problem with sharpness...

So another one for the photography gurus on the site...

I seem to be having an overall problem with sharpness with my A200 and the kit lenses (18-70 and 75-300). When I take pics of my dogs at close and even far range, they come out fantastic. Whenever I seem to get pics of planes even at relatively close range, when I zoom in on the pic it looks a bit fuzzy (some more than others). Now I know summer haze plays a part in this, but I was hoping for an improvement in the quality of my shots since I got the camera and I really haven't seen much. I generally am shooting F8-F10 when spotting, but even in good weather with great light, there just seems to be a general lack of sharpness and clarity in the shots.

So I guess my questions are: 1) Are all of your shots like that and you just know how to photoshop them?
2) Should I be looking into better lenses?
3) I know what most of your answers will be to this one - should I be looking into Canon or Nikon and not dropping money into Sony?

It's getting frustrating when I see so many of your shots coming out just superb and sharp as hell, while mine are just lackluster...any advice appreciated, and please feel free to point out any "driver errors" (meaning something I'm doing wrong).

EDIT: Also, I have one extremely stubborn dust spot on my sensor that the rocketblower won't take off. Any suggestions?

Some examples would help bro.

Will do, but I won't be able to post them until the weekend. Still in AZ...