Victoria/Greg:
Thanks for the help. You gave me the clues I needed. While probably not the cleanest way to do this it works. I'll work on neatness and efficiency in the future!
Add-Pssnapin Quest.ActiveRoles.ADManagement -ErrorAction SilentlyContinue
#Add-PSSnapin Microsoft.PowerShell.Core -ErrorAction SilentlyContinue
#Generate base account name of up to 8 characters in lowercase from CSV file removing spaces, commas and apostrophes
$Firstname = $SrcObj["First Name"].ToLower()
$Lastname = $SrcObj["Last Name"].ToLower().replace("-","").replace("'","").replace(" ","")
If ($Lastname.length -ge 8) {$UserName=$Lastname.substring(0,7)+$Firstname.substring(0,1)}
If ($LastName.length -le 7) {$UserName=$LastName+$Firstname.substring(0,1)}
#Search for Uniqueness in Domain
$Source = "DC=blah,DC=blah,DC=blah,DC=com"
#$Source = "DC=blue,DC=blue,DC=blue,DC=com"
$Name = $UserName
$defaultname= $UserName
$Exit= 0
$Count=1
Do
{
# Attempt to retrieve information on the user.
$User = $null
$User = (Get-QADUser -SearchRoot $Source -proxy -DontUseDefaultIncludedProperties -objectAttributes @{samaccountname=$Name}).samaccountname
If ($User -ne $null) {$Name = $defaultname + $Count++}
Else {$Exit = 1 }
If (($name.length -eq 9) -and ($Lastname.length -ge 7)) {$name = $Lastname.substring(0,6)+$Firstname.substring(0,1) + $Count}
If (($name.length -eq 10) -and ($Lastname.length -ge 7)) {$name = $Lastname.substring(0,5)+$Firstname.substring(0,1) + $Count}
If (($name.length -eq 11) -and ($Lastname.length -ge 7)) {$name = $Lastname.substring(0,4)+$Firstname.substring(0,1) + $Count}
If (($name.length -eq 9) -and ($Lastname.length -eq 6)) {$name = $Lastname.substring(0,5)+$Firstname.substring(0,1) + $Count}
If (($name.length -eq 10) -and ($Lastname.length -eq 6)) {$name = $Lastname.substring(0,4)+$Firstname.substring(0,1) + $Count}
If (($name.length -eq 9) -and ($Lastname.length -eq 5)) {$name = $Lastname.substring(0,4)+$Firstname.substring(0,1) + $Count}
}
While ($Exit -eq 0)
$Name
