Help validating non-model fields

I am sure this has been answered before, but a search of the interweb
didn’t return any solution.

I want to create a ‘Request for more info’ form which gets Emailed to a
site admin. This form will have name, Email and comments fields in the
view. Sending the Email is no problem - I duplicated the examples from
the agile book . What I can’t figure out is the “right” way to validate
that the name is filled and that the email field is a correctly
formatted
Email address.

What is the right way to go?

Many thanks in advance,

Matt.