Looks like you understand what you need to accomplish.
Here are two sample shots I did some time ago:
They were an exercise to show the difference in depth of field at two aperture settings.
As you can see, the darker setting f/8 gives the larger depth of field.
And of course ends up with the slowest shutter speed.
Which means a tripod is very necessary.
The delayed shutter release is best, to prevent jostling the camera.
In the sample photos, I used auto-focus and was focused on the side of the truck.
I was focused on the center of the O in the word CORN.
I was using ISO of 100.
The Canon A510 can be used as high as ISO 200 without getting objectionable noise.
The A510 does good at Auto White balance
If you are using tungsten or incandescent lighting, the A510 produces an orange cast to the photo.
So with that type of lighting, set the white-balance to tungsten for best color.
I suggest you use some measuring devices like I did in my sample photos, to see the range (front to back) you have to work with.
A tip: For large objects you can change your point of focus to get your model in the center of the "depth of field".
In my example, I focused on the nearest side of the model.
If I had focused on the center of the top of the truck, the depth of field would have more equally distributed (nearest to back most).
I know this doesn't quite fit in with the high-zoot SLR digitals usually discussed here, but I hope someone can help me. I do a lot of closeup shots for auction listings (so these images end up at screen resolution). My problem is depth-of-field while in Macro mode. As an example, I shoot a lot of diecast and slot cars, from 1/43d scale (pretty small -- 2" or less) to 1/12th scale (12" or more). If I shoot a 3/4-view in Macro mode (these things are small, with small details that need to be seen), sometimes the front of the item is perfectly focused, while the rear drops off in sharpnness. I'm trying to find a combination of shooting parameters that will keep everything in focus -- I've been using a very small aperture (like f/8) in Av mode, shooting strictly from a tripod (and delayed shutter release) into a light tent, which generally receives a combination of natural shaded sunlight and small halogen spots through the scrim of the lightbox (I never use the onboard flash for this kind of shot). I've tried auto white balance, measured (by the camera) light balance, adaptive focus, autofocus (but not manual focus... yet), AiAF off and on, full-auto mode with Macro mode selected, and have experimented with different ISO settings. Sometimes the results are OK, more often not, with the front-to-rear focus problems mentioned above. I've found the manual less than informative, to say the least. I'm hoping someone here can give me some ideas of a starting point for these Macro shots, including:
Shooting Mode (set with the Shooting Mode dial)
Macro Mode (set with the Macro/MF button)
Whatever else helps.
I thought I knew what I was doing -- my old Nikon Coolpix didn't have all these variables to mess around with, and I'm trying to get used to the Canon.