Finally I found a perfect monitor - calibrating is *ß˘$! :) - , so let's see a more useful post (I hope). What about object photographing?
All successful stock-photographers have two main themes - people and/or isolated objects. In my part I don't like to sell my family or unkownn people's faces, so object theme remains. I have no lightbox or professional flash (to tell the truth, I only have built-in flash and I rarely use it), but I'd like to take some "customer-friendly" photos (not only buildings and nature :)). I've known that I wouldn't be able to create isolated photos, so I chose an other way.
First of all, you should set up your cam. For most of pics you see in this article I didn't use tripod, so you also can do similar shots without it. Really important is the lighning - natural light or lots of lamps will help you to keep ISO low (highest ISO here is ISO320).Set white balance correcty and use lowest mm you have (easier to hold 18mm than 55mm, just step closer)...well, I think more useful will be if I stated the settings besides photos. :)
These roses were part of wedding-bunch of a friend. I simply took the vase and bouquet before a big french-window and asked her to switch on the lamps in room. ISO 200, manual WB (metering on chess-table's white), f/7.1, 28mm, canon bridge cam.
That was an easy issue. I was boring on my workplace, waiting for my colleueges... Some natural lights and a small table-lamp gave enough light. Background is a simple table. ISO320, manual WB (metering on card), f/5.6, 18mm - I could hold easily without motion blur.
First with I used flash. I've been in a japanese restaurant where ramen is not sooo tasty but looks really good, too. Auto WB (working good in s3is with flash), ISO80, f/8.0 (for details), flash, and I don't remember the distance, but I'll update it. :)
I had no enough light, so ISO320, 18mm, f/4.0, deep breath - and I could hold 1/15. :)
Some other advices, if you don't mind; for those who have only built-in flash like me - know your camera! Small flash is working good IF you know the perfect distance. Most of cams have hard noise-level steps - for example, my Pentax k10d has almost same noise-level in ISO200 and ISO 320, but noise drastically grow in ISO360. And, of course - always keep your lens clean, you can save hours in Photoshop. :)
First with I used tripod, so lowest ISO and mm/f as you like. :)
as Halient said below, if it's aviable, use RAW format. With it you can reduce the noise level effectively also.