I don't bother with entering the talk groups manually, I just let the radio scan and as the talk groups activate, I let the radio allow them to populate the list. If there is something I don't want to listen to, I hit the lockout button. Since you are new, that is probably the best for you right now. Once you have entered the frequencies in proper Logical Channel Number sequence, just let the radio do it's magic. Not all talk groups are active, in fact it may take months before you actually hear every single one. Some are not even used at all for whatever reason. Here is a tutorial on programming: http://support.radioshack.com/support_tutorials/communications/200-0524/67777.htm
The easier to read manual is here: http://myweb.cableone.net/marksscanners/94AB/94AB.html