I am having the worst time with these PHP forms. >.<

So, I got the majority of the code working really well, until my client decides to throw a curve ball my way and wants to add a field for the customer's order number.

I have the code to add the last name into the file name once it's uploaded to the server, but now I need to slap the order number into there as well.

HTML:
Code:
<p align="center"><img src="file:///Y|/LOGO/logo-custom%20camera%20collection%20small2a.jpg" alt="CustomCameraCollection" width="576" height="82"></p>
<table width="50%" height="121" border="3" align="center" cellpadding="5" cellspacing="0" bordercolor="#ccefef">
  <tr>
    <td height="119" bgcolor="#EAF4F4"> 
      <form name="onephotoupload" enctype="multipart/form-data" method="post" action="http://customcameracollection.net/customerphotos/upload_file.php" onsubmit="return validate_form(this)">
          <div align="center"> <font size="2" face="Verdana, Arial, Helvetica, sans-serif"> 
           
          <table width="100%" border="0">
            <tr> 
              <td align="left"> <div align="left"><font color="#003366" size="2" face="Verdana, Arial, Helvetica, sans-serif"> 
                  </font> 
                  <p><font color="#003366" size="2" face="Verdana, Arial, Helvetica, sans-serif">
                    <label><font size="1"><strong><font size="2" face="Tahoma, sans-serif">Please 
                    enter your order number</font></strong><font size="2" face="Tahoma, sans-serif">:</font></font></label>
                    <br />
                    <input name="ordernumber" type="text" id="ordernumber" size="8" maxlength="6">
                    <strong><font color="#FF0000" size="1" face="Tahoma, sans-serif">* 
                    Required</font></strong> </font><font color="#003366" size="2" face="Verdana, Arial, Helvetica, sans-serif"> 
                    <label> </label>
                    </font></p>
                  <p>
                    <label><font color="#003366" size="2" face="Tahoma, sans-serif"> 
                    <strong>Please enter the name the order was placed under, 
                    last name first, separated by an underscore.</strong></font><font size="2" face="Tahoma, sans-serif"> 
                    <font color="#003366">(ex. Smith_John):</font></font></label>
                    <br />
                  <input name="lastname" type="text" id="lastname" size="25">
                  <strong><font color="#FF0000" size="1" face="Tahoma, sans-serif">* 
                  Required</font></strong> <br /><br />
                  <font size="1"><strong><font color="#003366" size="2" face="Tahoma, sans-serif">Upload 
                  photo using the box below.</font></strong></font><br />
                  <input name="uploadedfile" type="file" id="uploadedfile" size="25">
                  </div></td>
            </tr>
            <tr> 
              <td align="right"> <div align="center"><font color="#003366" size="2" face="Verdana, Arial, Helvetica, sans-serif"> 
                  <input type="submit" name="submit" value="Upload Photo" />
                  </font> <font color="#003366">&nbsp;</font></div></td>
            </tr>
          </table>
          </font></div>
        </form></td>
  </tr>
</table>

PHP:
PHP Code:
<?php

$target_path 
"uploads/";

$target_path $target_path rawurlencode$_POST['ordernumber']['lastname']); 

$target_path $target_path basename$_FILES['uploadedfile']['name']); 

if(
move_uploaded_file($_FILES['uploadedfile']['tmp_name'], $target_path)) {
    echo 
"The file ".  basename$_FILES['uploadedfile']['name']). 
    
" has been uploaded.";
} else{
    echo 
"There was an error uploading the file. You can email us your photo as an attachment at cameras@customcameracollection.com.";
}
?>
What I've got going on is not working. Forgive me if I've completely butchered the PHP in the process.

Also, if there's any way to put some code in the there to be able to easily separate the order number, name, and file name with an underscore? Greatly appreciated.

TIA.