i really like speer #13...
but, some of your questions either aren't explained, or you can get better explanations on various forums.
for a wealth of reloading knowledge, check out the forums at:
www.baitshopboyz.com/forum
www.24hourcampfire.com/ubbthreads/ubbthreads.php
www.handloadersbench.com
also, get sierra's number. it is an 800 number, and those guys can answer about any question you can dream of. they also respond via e-mail. best thing is, they don't care if you are using their product or not, they will help you anyway.
quick answers: some bullet/powder combinations aren't listed because in some cases there are so many conceivable combos, they cannot all be covered, or in some cases (speer, hornady, nosler, hodgdon, barnes), they want you to buy their stuff, so they will only show you their products.
don't try to calculate loads yourself. start w/ loading manual data, then experiment from there. this process takes time and is best learned by hands-on.