Handles are processed by the games staff, and this can usually take up to 24 hours to be approved.
If your handle request has disappeared, chances are it has been declined, and you will need to submit a different handle for approval which follow the Character Creation (Handle) rules (Clicky).
If it has been approved, you will see: "APPROVED" wrote on the page, in green (As shown). This means you can go ahead and create your character.
If you have any problems with your handle (Eg. It has been more than 24 hours since you requested it), please submit a Support Ticket (http://support.swcombine.com) where someone can look into it for you. Please do not submit a ticket before the 24 hours is up.