Most conventional communications networks today, particularly existing telephone networks, provide a calling party with an audible ringback signal when an intended called network address or station line is idle and a busy signal when the intended called network address or station line is already in use (i.e., the telephone or other device at the called network address is being used).  Conventional networks also provide a calling party with an audible dial tone signal when the telephone or other device at the calling station signals the network that they wish to initiate a call or network communication and a line is available.  Most conventional communications networks today, particularly existing telephone networks, also provide advanced features, such as call waiting.  The call waiting feature allows a station or device already connected to another station or device to temporarily disconnect from a first call and receive a second incoming call, and then switch between the calling parties. 
For example, U.S. Pat.  Nos.  5,557,658, 5,428,670, and 5,321,740 to Gregorek et al.,  incorporated herein by reference, disclose the selective modification or replacement of at least a portion of a call progress signal, including the conventional aforementioned ringback signal, dial tone, busy signal, call waiting signal, and call waiting idle time, with prerecorded announcements and/or audio/video programming.  These announcements and/or programming provide more information to a calling party.  The replacement announcements and tones can be tailored to a specific calling party and can be associated with a calling party's unique network address or telephone number. 
Custom ringback announcements allow for an additional level of flexibility and personalization of a user's communications network service.  To customize the system, a user of a replacement ringback system, the network provider, or a third party might wish to deliver, for example, audio/video programming, music, interactive games, jokes, personalized messages, or informational messages to a calling party to supplement and/or replace the conventional ringback tones played to the calling party.  Furthermore, replacement content can be customized for a specific calling party or group of calling parties.  The replacement ringback system offers a convenient and simple way to extend a caller's communication experience and takes advantage of a previously unutilized call transmission period. 
In addition, replacement ringback tones and announcements offer almost limitless applications in the marketing industry.  Typically, a caller experiences a rather large amount of unused idle time when waiting for a called party to answer his or her telephone.  A caller may also be put on hold for several minutes while the called party answers another inbound call (e.g., a called party may place an initial caller on call-waiting or hold to answer a second inbound call).  Since ringback tones can be played to all parties, regardless of the called party's or calling party's own carrier or calling transmission means (i.e., whether the caller is calling from a wireless link or land line, etc.),  replacement ringback tones are an ideal medium for advertising.  Substantial revenue can be gained by taking advantage of this idle time to deliver advertisements pertaining to consumer goods, products, services, etc.  provided by a particular corporation or individual.  Further, since communication devices are virtually ubiquitous and universally used, ringback tones have the potential to reach a large, targeted audience very quickly and efficiently.  For example, businesses may use replacement ringback tones to deliver company slogans, jingles, and promotions to increase exposure and publicity. 
As the adoption of the technology identified in the above-referenced application is emerging, certain drawbacks in the user interface for enabling the functionality of the application are arising.  For example, a subscriber is usually required to notify the network provider in advance if the subscriber desires a new ringback replacement association via a Short Message Service (SMS) message, email, or telephone call to the communications network's voice response system or call center.  This advance notification, for example, usually contains at least the network address or addresses to be associated with the new ringback content and an identification of the desired replacement ringback content.  Alternatively, a communications network may utilize a website designed to facilitate interaction with the network's ringback replacement system.  After an authentication and identification process, a user of a replacement ringback website may specify new ringback content to be added to the user's ringback service via a user-friendly web interface and a series of graphical prompts and menus.  The desired ringback content may be already stored on the communications network (or a third party location) or the user may select local content to be transferred to a storage location accessible by the communications network.  The website may utilize standard HTTP upload functionality, File Transfer Protocol (FTP), or any other data transfer or upload mechanism to initiate the transfer of the replacement ringback content to the communications network.  The network provider then makes the necessary changes to the subscriber's service to associate the appropriate network address or addresses with the desired ringback content. 
Also, notification and confirmation by external means are often required to update or change the ringback content for an already-existing ringback association.  For example, an exchange of emails may be required to effect the change in service, or a visit to a website may be necessary to modify replacement ringback functionality.  This often inconvenient and time-consuming method of updating or adding new ringback content to a user's service discourages subscribers of a ringback replacement service from frequently modifying or adding new ringback replacement associations, thus reducing potential revenue by deterring regular and repeated ringback content purchasing and utilization. 
In addition, many communications networks interconnect several different carriers (such as a prepaid calling card provider or long distance carrier, or other like provider).  The party placing a call is often handed off to a different, intermediate carrier, which may ultimately terminate or complete the call.  In some instances, the intermediate carrier may be chosen by the calling party (e.g., when the calling party places a call using an access number printed on a prepaid calling card).  In other instances, the communications network hands off the caller to another carrier or provider without the calling party's knowledge.  Often times this handoff is performed to provide an enhanced service to the calling party, such as advertising services that queue a caller within a congested network until an automatic call distributor (ACD) becomes available. 
It would be advantageous certain custom replacement ringback announcements could be delivered to incoming callers in a multi-carrier environment.  It would also be advantageous if subscribers of a replacement ringback service could utilize a simple system for modifying or adding replacement ringback content to the subscriber's network service.  Thus a seamless service is needed for delivering custom replacement ringback content in a multi-carrier or enhanced service environment.  A system is further needed for easily customizing this service using a familiar means, such as the menu or prompt systems already integrated with a handset or station or a user-friendly web-interface.