MicrostockGroup

50,000 digital shots doesn't cost nothing. You probably have to buy a stand-alone hard drive or two to store them and if you are going to get much benefit from them you need to review each shot for, say, 10s to get an idea about the depth of field, choice of focus point, effect of lighting etc.  Half a million seconds is just about an half a year of your life gone, working eight hours a day, just to glance at each pic for 10 seconds.  [I've just realised why I have such a mountain of old digital photos sitting on drives that I have never got round to sorting out, including stuff that might sell well].

Hammering off tens of thousands of shots without thinking about them doesn't teach you much. Shooting a thousand or two, thinking carefully about what you are doing and why, is likely to be a better education. Of course, you can do that with digital just as easily as with film but the temptation is to machine-gun shots and hope for a lucky hit.

Still if a decent secondhand DSLR and lens can be had for as little as $300 then it would be more in keeping with the zeitgeist.

My 2p on the advice you've had above:
"Aesthetics and commercial" - in stock, commercial trumps aesthetics, but of course, some aesthetics matter, in particular, not cluttering your image.
"Camera clubs" - I'm actually a happy member of a camera club, but they're all about aesthetics/pictorial, so I show the photos I love there, >80% of which I wouldn't submit to micro. They generally don't obsess about really nitpicky technical issues, so you can get a shock when you hit micro and get rejections for things you didn't even know existed! Once we had a speaker didn't turn up, and the chairman grabbed me as I went in the door and asked if I could talk about 'something photographic' - well, with no warning and no slides or powerpoint, all I could think of was iStock, so I blahed on about that for about 20 mins. The next week, several members said, more or less, "I had a look on iStock and the pics there that sell well wouldn't do well in competitions". I had to say the vice was also very much versa.
Camera: buy into Canon or Nikon second hand for more flexibility later on. You need a 'decent' camera body, but the quality of the lenses is even more crucial. It's hard to know what your first lens should be. Many people will tell you to get something like a 50mm f1.8, so I'm guessing many people use that sort of lens, but it would be almost useless to me. If I had to have only one lens for myself, it would be a 100-400 zoom, but for micro, I use my 24-105 most. YMMV.

Will,

Does your current camera allow aperture and shutterspeed priority and manual exposure? Does it allow white balance adjustment? Does it have the option to show an histogram?  

Many compacts these days have these options, and I think this is the basics to get you started in photography and improve your current skills, and as you advance you may go on buying an used DSLR as suggested here, or even a new one if your budget by then allows it.

Well, like everything, it will depend on the agency and the reviewer and whether he had a punch up with his girlfriend last night.  But with a cheap zoom I think you would need to avoid all the extremes - avoid the widest wide angle, avoid pretty much every aperture except f/5.6 and f.8, then, yes, it would probably be satisfactory. Also, you can be lucky or unlucky with a lens/camera combination. If they happen to be a good match they will do better than if they aren't.

Fair enough.

Looks like you are getting some good advice here, so good luck!

THNX for advice but Willy must change his pampers now so he will not be available for a while.

I think you lose sharpness on most lenses when you go much over f9, around 7 is usually the sharpest aperture.

Yes, that's why I suggested sticking at around f/5.6 to f/8

It's not the fault of the lens, it's to do with the aperture itself and the size of the sensor/the magnification for viewing. Every lens is the same in this regard

The camera I am currently looking at is a Canon EOS 1100D, which comes with 18 - 55mm lens. I think it should be adequate for starting stock photography, in the future I will be able to upgrade lenses to a 75 - 300mm lens if needed.

@Baldricks:
Funny you should mention a film camera, my granddad offered one to me last week. He says it was a very good quality camera that my father use to own. I think I shall give it a try, it will be a good learning experience for me.

I guess I know what I am saying, you might know too but on studio I play with high F and it worked very nice and I do test quite often and compare results.. I am sure I am not the only one playing with high F, if I have enough light I go up if not I go down keeping the ISO always at 100 unless one or two exceptions.. the 50mm doesn´t need that high F I know but I like to pump it up, I am not getting rejected for focus or other so I am not doing anything wrong at least in shooting

Yes, why not run a couple of rolls through it, if you have a free SLR camera on offer. At least you will get the feel for how it works.

In addition, if it is either a Canon EOS camera or any kind of Nikon SLR then any lenses it has got with it should fit today's digital Canon or Nikon digital cameras. They may or may not have autofocus, depending how old they are, but if you can get good glass for free then it might be worth buying a camera body that fits on the glass since a high-quality lens can easily cost more than a modern DSLR body and the lens will last pretty much forever.

The EOS1100D is a good camera, of course. I had the first version of the 75-300 and it was a horrible lens. At 300mm the aperture was only f/5.6 which meant it needed long exposure times (and at 300mm you want short times to avoid camera shake) and because the viewfinder was dark (due to the small aperture) it was slow to autofocus and hard to focus by hand. They've probably improved autofocus since then but a slow, long lens is pretty limited.

The trouble with cheap modern AF lenses is that you still have to pay for the internal motor to drive the lens, so the manufacturers have to save money on the rest of it, including the optics.  The expensive 24-70 and 70-200 lenses are much better. You probably won't use 300mm on a crop-sensor camera, anyway. 24-70 or 24-105 is likely to be much more use to you (and the 24-70 is the better lens from Canon, judging by reports comparing it with the 24-105).

Very big zoom ranges appeal to newbies because it sounds great if you can get all that magnification in a single lens .... but there is a heavy price to pay in image quality, because the longer the zoom range the harder it is for the designers to control all the different distortions that light suffers from as it passes through lenses.

A major factor for me in choosing a camera, is its feel. I am really fussy when it comes to how good a camera feels in my hands. A lot of people shoot with Canon 500d or 550d. I find them really awkward to hold, the body just seems too slim (and I don't have big hands), I imagine the 1100D is similar. I was playing around with a Canon 50D in a shop recently and that just feels so right. I currently have a Pentax K-x, which is a pleasure to take photos with.