Shell Programming and Scripting

I'm trying to write a bash script to perform a tedious task, but I have no experience and hardly any knowledge so I've been having a rough time with it.
I'm on Mac OS X, and I want a script to do the following:
I have a directory that has about 200 sudirectories. In each of these directories, there are a number of html files that each include a relative link to an image.
What I want to do is create one html file that contains all the img tags of all the html files in all the sudirectories. I would also like to turn all the relative links into absolute ones (meaning: I want each src attribute to contain the full path on my system of the html file -and image, they are in the same directory-).
I've been at it with sed, but one of the problems seems to be that some of the html files don't have regular UNIX line endings, so it's kind of hard for me to extract just those line with img files (I get the full files), let alone img tags.
What I've been toying with is the following (where you'll see that I try to put some line endings back where I think they'd be useful - though for some reason it doesn't work as expected):

#!/bin/bash

for pic in ./advanced/*/image??.html
do
grep img $pic | sed "s/img/img\
/" | cat >> images.html
done

This script doesn't address the absolute link problem yet.

Any help would be greatly appreciated.

Just a couple of ideas....

For the end of line problem, use tr or dos2unix (if applicable and installed) to replace the end of line characters with \n.

For getting the absolute path, have a look at "dirname".

Cheers
ZB