There is a perspective that TCL-IVR applications are not flexible enough for a newbie to play around. But in fact, there are lots of IVR applications that are coming inbuilt with Voice GW. You just need to copy/paste in a file editor and tweak it.
The recent hype is for BACD IVR applications. They are coming inbuilt with 12.4(15)T and later. Most of the enhancements are done with BACD AA application and that too coming inbuilt you can very easily play around with. Its easy to modify it to suite a big call centre/customer support kind of environment.
Just issue "show call application voice summary" to see all the inbuilt TCL applications. Happy IVR-ing :-)!!!