Using an automatic setting or "close-up" mode does not really work when photographing miniatures. Though when I take photographs at shows using my Canon EOS 400D I generally do use the "automatic" mode.
When capturing such small items on film, there are two key points: depth of field and lighting.
Depth of Field
The simplest way to explain this, is depth of field is how much of the scene is in focus.
With a low f stop (or large aperture), something like f5.6 you will have a shorted depth of field (less in focus) than if you use a higher f stop (small aperture).
The aperture is how wide the lens opens for letting light in. A low f stop means a wide opening, a high f stop means a narrow opening.
Virtually all my photographs (digital excepted) are taken on the highest possible f stop setting (in other words the smallest aperture possible).
Depending on the lense you are using, this should be from f22 to f32.
As a result and depending on lighting this means very little light is getting through, therefore to compensate you need to leave the shutter open for longer.You are looking at a shutter speed of 2" to 4" (as in two to four seconds), therefore a tripod is essential.
This is a shot using an aperture of f 5.0 with a shutter speed of 1/6th of a second. Notice how blurred the rear and front Orks are.
This shot uses an aperture of f 32, but a six second shutter speed, notice how all the Orks are in focus.
I would not recommend using a direct flash as it "washes" out the colours. You can use professional lighting equipment or bounce the flash off a piece of card; however, I generally use a desk lamp, with a blue filter on the camera to compensate for the "yellow" effect of the normal lightbulb.
If you don't have filters, then you can use software on your computer to enhance the image and remove the yellow cast.
You can also see how much closer you can get when using extension tubes, see details on the next page. Extension tubes literally allow you to get the focal length down to less than quarter of an inch, whereas without them it may be as much as twelves inches.
The EOS 400Dis nice in that it allows us to set the apeture but lets the camera set the shutter speed (depending on the speed of the film), however the full manual capability is also available and useful for certain shots.
Most digital cameras have a close-up mode (look for the tulip) but they are certainly not as flexible as a full manual SLR camera and generally the tulip mode does not increase the depth of field it jsut reduces the focal length (ie allows you to get in closer).