powershell script to copy mutliple files into a single file
PS C:\temp> $mergeFile = "c:\temp\merged.file" # path/name of your merge file
PS C:\temp> Get-ChildItem -Filter *.txt | foreach {
$_.fullname | out-file $mergeFile -Append # append current file name to merge file
get-content $_.fullname | out-file $mergeFile -Append # append current file content}