SELECT() using todays date not working

[TedM]

I have two tables - "Visitors" and "Phone No.s".

When someone creates a new entry in Visitors I want to check the number they are entering hasn't already been entered (in Phone No's) that day. 

I'm trying create the list to check against using:
LIST(SELECT(Phone No.s[Number],date(TODAY()) = DATE(Phone No.s[Date])))
but when I test it I'm not getting anything in the list.

Phone No.s[Date]