Extracting Google Check out email address

[devicode]

How do I extract the purchaser's Google Check out email address from the message body.

Subject line "Purchase Receipt for Order #".

Body text
Hello googleorder@somwhere.com,

puchaser-email@checkout.google.jam has just completed a purchase from
your store.

[devicode]

Create field EmailAddress.
# Start of Data Field'
For the FROM select 'Specific text'
For the TEXT enter Hello(.*?\n)(.*?)has just completed
# 'End of Data Field'
For the TO select 'Use Match String'
For the TEXT enter 2