Welcome to the forum. Nice to see another person taking an interest in the CB's
Will try and answer some of your questions. The 19 channel is historically used for a calling channel, and once you have made contact with someone it is the norm to move to another channel to keep 19 clear. You may find however that alot of people stick on 19 and hog the channel chatting, so sometimes it's worth just scanning through the range of channels seeing if you can find a chat that you might be able to jump into the side of. If you find a chat that you want to join in on, just wait for a sutiable break in the chat and then politely ask if you can join in.
As for info on getting the best out of your aerial I would definatly suggest getting an SWR meter and linking that into your rig to make sure you are getting the best performance out of the aerial possible. You basically plug the aerial into the SWR meter and then another patch lead out of the meter and into the CB. I've included a couple of videos from Youtube which give you some more info on setting up and using the SWR Meter. Once you have set up the aerial, take the meter out of the loop of else you could lose some power from the trasmittion.
Part 1 -
http://www.youtube.com/watch?v=FLJj3QGW ... re=related
Part 2 -
http://www.youtube.com/watch?v=bl0vnjiI ... re=related
Cant help you with finding people in your area. I'm from Nuneaton so very very much doubt you would get enough range to get me. The best advice I can give would be to get some height. The heigher you are the better your transmit range is going to be. Thunderpole has a map showing CB users who have registered on the map, which you can find here
http://www.thunderpole.co.uk/user-map.html hope some of this info is of help to you.
Catch you later good buddy.