Applescript Help Assistance - add IF statement

I have put together this applescript that when a file is added to an action folder, it makes a new directory based on the first portion of the file name, makes a directory called 'images' inside, and then Moves the input file to the 'images' folder inside the newly created folder. This all works GREAT, UNTIL. .dun-dun-dun.. The directory exists already!! (oh no) . So I tried adding some If statements and it still is running the rest of the script fine (which adds in some other files and moves the completed folder set to another folder on my hard drive), but I can not get the file with the same first portion of the name to Move or copy over.. It needs to add an IF Folder exists somewhere and trying to figure it out, but can not get this to work. Any help appreciated. Here is the code: tell application "Finder" activate set target of Finder window 1 to folder "MAKER" of folder "Desktop" of folder "nathan" of folder "Users" of startup disk make new folder at folder "MAKER" of folder "Desktop" of folder "nathan" of folder "Users" of startup disk with properties {name:fileName} set target of Finder window 1 to folder fileName of folder "MAKER" of folder "Desktop" of folder "nathan" of folder "Users" of startup disk make new folder at folder fileName of folder "MAKER" of folder "Desktop" of folder "nathan" of folder "Users" of startup disk with properties {name:"images"} set source_folder to folder "new-actiontester" of folder "Desktop" of folder "nathan" of folder "Users" of startup disk set source_folder_list to folder "img-list" of folder "Desktop" of folder "nathan" of folder "Users" of startup disk set source_files to every file in source_folder set source_files_list to every file in source_folder_list set target_folder to folder "images" of folder fileName of folder "MAKER" of folder "Desktop" of folder "nathan" of folder "Users" of startup disk set target_Go to folder "GO" of folder "Desktop" of folder "nathan" of folder "Users" of startup disk set folder_Number to folder fileName of folder "MAKER" of folder "Desktop" of folder "nathan" of folder "Users" of startup disk set target_folder_list to folder fileName of folder "MAKER" of folder "Desktop" of folder "nathan" of folder "Users" of startup disk repeat with i from 1 to number of items in source_files set source_file to (item i of source_files) move source_file to (target_folder) -- use "copy source_file to folder (target_folder as alias)" to copy the files end repeat repeat with i from 1 to number of items in source_files_list set source_file_list to (item i of source_files_list) copy source_file_list to folder (target_folder_list as alias) -- use "copy source_file to folder (target_folder_list as alias)" to copy the files end repeat copy folder_Number to folder (target_Go as alias) -- use "copy source_file to folder (target_folder_list as alias)" to copy the files end tell