Can't help you with automator, but you can create an app with the applescript below that will do what you want.
Procedure:
1. Open the Applescript Editor by typing Apples in the spotlight search field and hitting 'return' on your keyboard.
2. Copy the entire script below and paste it into the Editor window.
3. Hit 'Command-K' on the keyboard and ensure there are no compiler errors. If there are, please look at the script and see if one part of it was highlighted. Report back what part of the script was highlighted and any error messages.
If the compile didn't produce an error, then:
4. Hit 'Command-S' on the keyboard, choose a snazzy name ("PDF merger" or something...) and a location to save it in (your Apps or Desktop folders). Be sure to change the 'File Format:' to Application at the bottom of the Save screen before hitting 'Save'.
5. The first time you run the app (you run it by double-clicking on it, like any other App), you'll be asked to put in the details manually. On subsequent runs, it will fill in the defaults for you. I haven't set up the default locations for looking and searching for the files as I'm not sure where they would be on your system. I can do that if you tell me the path from your 'home' or user directory.
Also note, I've written the script so that it doesn't send the message until you've reviewed it. i.e., you might want to double check you've attached the correct file, or add a message. If you want it to send automatically without review change the following lines near the end of the script:
change the line 'set visible to true' to 'set visible to false'
change the line 'save' to 'send'
property defaultFolder : ""
property msgSubject : ""
property theRecipient : ""
property theWeeklyname : ""
property outputFile : ""
getInfo()
mergePDFS()
sendMail()
on getInfo()
display dialog "Type the recipient's email address: " default answer theRecipient
set theRecipient to the text returned of the result
delay 0.25
display dialog "Set the subject of the message: " default answer msgSubject
set msgSubject to the text returned of the result
end getInfo
on mergePDFS()
display dialog "Please choose the files to merge…" default button "OK"
set inputFiles to choose fileof type "PDF" with multiple selections allowed without invisibles
delay 0.25
display dialog "Please choose a folder to save the merged PDF…" default button "OK"
set outputFolder to choose folder
delay 0.25
display dialog "Type the name of the combined pdf (without the .pdf extension): " default answer theWeeklyname
set theWeeklyname to text returned of the result
set outputFile to (outputFolder as text) & theWeeklyname & "(" & (count of inputFiles) & ").pdf"
set pdfFiles to ""
repeat with p in inputFiles
set pdfFiles to pdfFiles & " " & quoted form of POSIX path of p
end repeat
do shell script "/System/Library/Automator/Combine\\ PDF\\ Pages.action/Contents/Resources/join.py " & "-o " & quoted form of POSIX path of outputFile & pdfFiles
return outputFile as alias
end mergePDFS
on sendMail()
tell application "Finder"
set theAttachment to outputFile as alias
end tell
tell application "Mail"
set newMessage to makenewoutgoing messagewith properties {subject:msgSubject, content:"" & return & return}
tell newMessage
set visible to true
makenewto recipientat end of to recipientswith properties {address:theRecipient}
tell content
makenewattachmentwith properties {file name:theAttachment} at after the last paragraph
end tell
save
end tell
end tell
end sendMail
