Sounds like you need XML::DifferenceMarkup and one or more of the many, many email composition and sending modules.

format them in such a way that they can be easy to view

This suggests that you don't yet have a real spec, since "easy to view" is very subjective. As ever, the process should be:

1. Detailed spec
2. Algorithm
3. Tests
4. Code

(although you might promote Tests to 2 if you fancy it)

See also comparing XML files.

I still use the following bash script to compare XML files and usually find its output informative enough, if not more readable than various XML oriented diff tools.

#!/bin/bash

a=($@)
b=$#
f2=${a[$((--b))]}
f1=${a[$((--b))]}
diff "${a[@]:0:$b}" \
   <(xmllint --c14n "$f1" |xmllint --format -) \
   <(xmllint --c14n "$f2" |xmllint --format -)
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($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,
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Which part do you have problems with?

There is XML::Diff and/or Algorithm::Diff, depending on what kind of diff you need for your XML.

For mailing, there is MIME::Lite, which makes it easy to send attachments.

I am getting this error: Can't locate XML/Diff.pm in @INC upon using module XML:Diff ?

This isn't a core module, so you have to install it:

cpan XML::Diff
or
cpanm XML::Diff
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