Exception write to event log when user not found in active directory

Question

I'm trying to use a exception to write to a event log to show which user did not get imported from my csv file. Any help to write this exception is appreciated. Thanks
Import-CSV $importfile | ForEach-Object{
$samaccountname = $_.sAMAccountName.ToLower() #samaccountname on csv file
Try {
$exists = Get-ADUser -LDAPFilter "(sAMAccountName=$samaccountname)" #Filter user by samaccountname
Catch
write-host "Users did not exist." #user does not exisit

Answer 1

To your question:
"How can I create a new event log every time without saving to the original event log textfile?"
The answer provided by Mike Laughlin doesn't require you save anything to a text file - so either I'm misunderstanding this follow-up, or you are misunderstanding Mike's post. :)
To answer your other follow up... try:
$goodCount = 0
$badCount = 0
Import-Csv $importFile | ForEach {
$SamAccountName = $_.SamAccountName
try {
$user = Get-ADUser -Identity $SamAccountName -ErrorAction Stop
$goodCount++
} catch {
Write-EventLog # <-finish this command however you want
$badCount++
write-host "Users imported: $goodCount"
write-host "Users not imported: $badCount"
G. Samuel Hays, MCT, MCSE 2012, MCITP: Enterprise Admin
Blog:gsamuelhays.blogspot.com
twitter:twitter.com/gsamuelhays