I wrote some kind of an assassin guide on this forum that was mainly focused on newbie assassin trying to run away and hide. And to explore the world successfully. There may be other assassin guides around, but I don't remember them. Can't remember how to make a link, but the guide can be found from:

http://forums.carrionfields.com/dc/dcboard.php?az=show_mesg&forum=5&topic_id=589&mesg_id=596&page=2

Oh, and when it comes to shield block and dual wield, use shield when you are fighting in front row and dual wield another weapon(felars dual wield their claws, meaning the other hand is left empty) when you are fighting in back row in the group.

The following is generally true in CF:

In this MUD, people tend rank in groups of three people. You should practice all weapon skills and defenses(dodge, parry, shield block and unarmed defense) to 75%(which can be done by putting two practices to it, unless you are arial or some other smart race, in which case you should get +int gear or max your int by training it. After that, you'll only need 1 practice to get it to 71%(int=23). Constitution should be kept as maximum too for maximal hit point gains/level. Also, have natural wisdom stat at at least 18 to get 3 pracs/level). The easiest way is to put two practices to every skill you have, so that they would work reliably when they need it, as you are new to the class and don't know which skills you are going to need.