Ravish,
In this situation you are might be SOL, with out using an EDM.
There is now way to detect Frist Name or last name, unless you just search for the terms "First Name" and "Last Name". With the hope that those terms are in the spreadsheet as a column heading.
Though you will probably get a ton of False positives.
As far ar Email addresses go, you can create Regex to look for the email format. Though it will trigger on email address that are in the body of a message, especially when it comes to email conversations that have replies and a ton of email addresses in them.
In order to reduce the false positive rate of email matching you will need to set the match count pretty high.. 25+ and you will still get some false positives.
Overall in order to do this you will need an EDM extract to be imported. (First, Last, Email, Zip, phone) Get the extract from Salesforce and use that or an AD extract. Then when you create the EDM policy match it on 3 of the 5 fields. With a match count of 3 or more.
This will give you the best accuracy and least amount of false positives.
Hope this makes sense.
If this solves your questions please marked as solved.
Ronak