I took pictures of the sideart of a Ms Pacman / Galaga class of 81 cab. I have to say one picture of the whole thing wasn't enough detail for me. But then I have a measly 3M pixel camera. I took 4 overlapping pictures and stitched it all together (actually I have 4 base images in CorelDraw).
Keep in mind that a 3M pixel camera is in fact maybe 2M camera (or maybe even just 1M). The "pixels" in the CCD element are in fact just pixels of 1 base color (of which there are 4 for a full "screenpixel", usually 2 green, one blue and one red). That's why when you zoom in to a digicam picture to "actual pixels" the picture always looks blurred. They cheat and create the color of each "pixel" by taking adding the colors of the surrounding pixels. But then you just reuse information.
I used PaintShop pro 8 to straighten out the pictures. If you can, try to make sure you get some horizontal and vertical lines around the image (and maye in the area's that you are cutting). That will make the straightening out the pictures a lot easier.
Most camera's will suffer from some pincushion or barrel problems (depending on the zoom level). Paintshop pro can also correct this. Again getting horizontal and vertial lines will help detect this problem and in correcting it.
Adobe Photshop 7 will do some straightening and perhaps even lens corrections, but I found it much more cumbersome. Maybe Pohtoshop CS is better. With paintshop pro you select the corners of the image and it corrects it back to adjust out the perspective. With Photoshop you have to drag the perspective out (in fact photoshop is made to ADD perspective rather than take it out)
What also helps is if you can find a picture of the artwork on a site like twobits.com. They often have the artwork in perfect alignment. I blow up that image and place the pictures I have taken, onto this base image to make sure they are aligned just right. I use a tranparent layer to overlay my pictures on the base image and fiddle with them until they align.
It also helps to take some detail pictures of really complex areas, even if just to make sure how things should look.
Another thing is to bring a color chart to check the colors. It's pretty hard to get accurate colors back from digital pictures.
BTW, for tracing I find CorelDraw a lot easier to use than Illustrator, but that's just me perhaps. I hate the lack of context menu's in Illustrator. Corel has a line draw view where you just see the centerlines of the strokes and no filles, but it show the bitmaps. This view is excellent for finely adjusting lines. I also like to just place a lot of dots along a line and then let Corel smooth them out and autoreduce the number of points.