Wendy,
I'll try to answer your questions as best I can,you don't want to cure these pickles overnight,the glory of these pickles is there crispy,crunchy texture,be sure in canning that your jars are hot and your infused vinegar is hot when you add it to the cucs and then add them right to the canner and boil for those 15/20 minutes I told you.
Be sure that the lid that you seal down has become "sucked down" by the vacumn action of the canner and has no give at all when you press down on it.
As far as pickling spice, I crush bay leaves,juniper,mustard seed,pepperflakes,black peppercorns,crushed coriander,toasted fennel seeds ETC,ETC,ETC..or you could go out to the spice rack at your local store and pick up a bottle of pre-made mix.
Wendy,
If you have any questions grab some books from your library,because following the proper pickling procedures is very important as you know.
Happy pickling