Extracting is a time-consuming job, for sure, and I don't know any way around it, but there are some tips for extracting using various tools, channels, and masks. You can Google tutorials for this (see especially the ones done on the Photoshop Roadmap series, and Deke McLelland's video tuts) and add to your arsenal of techniques.
Personally, the tools I use the most are the polygonal lasso and pen tool for selecting areas to delete, then a meticulous course around the object with a small eraser. Use a set of Quality Control styles/actions to check your progress, getting rid of stray pixels, dark or light edges, etc.
For the purposes of some layouts, a blended photo, without full and careful extraction, will suffice, and be a whole lot easier. You can use gradients to soften the transition between the background and the image, or use a very soft-edge eraser to get rid of the large background areas around the image (see this month's Photography Challenge for examples).
With respect to recoloring b/w or sepia-tone photos, you can only really tint the whole photo, like applying a photo filter or color balance adjustment, or you can use the color replacement tool to add color to a particular part of the image (be sure to change the mode of the photo from grayscale to RGB first). This would look like the old hand-tinted photos of the past, and can be effective if not used with a heavy hand.
Last edited by donakat; 01-15-2012 at 11:57 AM.