With this script you can search for a nick/address using $ial (internal address list).

Usage:

/faddr matt*
Result:
matt* (1) on freenode is:
1) Matt5150 - ~Matt@unaffiliated/matt5150

/faddr *@unaff*
Result:
@unaff (21) on freenode is:
1) alphis - ~noone@unaffiliated/alphis
2) andmars - ~andreas@unaffiliated/andmars
3) Daekdroom - ~Daekdroom@unaffiliated/daekdroom
ecc.. ecc..

Note: works on muli-networks, type /scid -a faddr *test*

alias faddr {
  if (!$window(@Address)) { window -azdBke2 @Address $calc($window(-1).w /2 -250) $calc($window(-1).h /2 -125) 500 250 }
  if ($1) { search.addr $1- }
}
on *:INPUT:@Address: { if ($left($1,1) != /) && (!$ctrlenter) { search.addr $1- } }
alias search.addr {
  var %:adr = $1-, %:a = 1
  aline -h @Address $chr(160)
  $iif($ial(%:adr,0),aline -h 4 @Address %:adr $+($chr(40),$v1,$chr(41)) on $network is:,aline -h 4 @Address %:adr no address found on $network)
  while (%:a <= $ial(%:adr,0)) {
    aline -h 15 @Address $+(%:a,$chr(41)) $+(14,$ial(%:adr,%:a).nick,) - $ial(%:adr,%:a).addr
    inc %:a
  }
}